None of what you list requires two separate OSs, although of course having two separate OSs is a way to implement this. Having users and users data isolation is perfectly possible on a multi-users OS and been done in practice, although not in a mobile environment. The independent management support can also be done by trusted software on the single OS.

An hypervisor really becomes the required approach if one must have two different OSs on the same device. There the multi-users OS falls short. But I wonder how practical it is in this context: you want the user to have similar environments in both professional and personal mode.

The hypervisor approach makes sense when two very different environments must share a CPU. For example, a very limited secure environment (limited to be small and easier to verify) and a regular OS. To simply split professional and user environments it seems overkill.

The pricing is not so much driven by the technology than by what operators can charge. It's particularly true for text, where the margin is really really huge and unrelated to technology. But as it's a geek site let's go over the tech now ;) All 3 use slightly different mechanisms.

Short messages (SMS, or text) piggy back over the signaling protocol.

With GSM and WCDMA 3G (3GPP standards), voice and data share the same radio network. But on the network side there are separate core networks for voice (CS domain, for Circuit Switched) and data (PS domain, for Packet Switched). In the CDMA world there are actually separate radio networks for voice (CDMA 1x) and data (EVDO). This is why you can't do both voice and data at the same time on most CDMA phones: it would require 2 radios, which adds cost and complexity. Whereas with 2G/3G, both goes over the same radio network so both can operate concurrently with a single radio.

Starting with 4G, or LTE in practice, there is still a single radio network as before but now the core (EPC, Evolved Packet Core) is also unified and built over IP. Voice over LTE (VoLTE) is not common yet but it's basically VoIP built on IMS. All is unified, but voice is of course prioritized over best effort data using QoS both in the RAN (radio access network) and EPC.

Yes, and even less than that I'd bet. The latest ARM implementations, whether Cortex A15 or Krait, are already hitting a thermal wall. When benchmarking the latest Qualcomm quad-core S4 based on Krait on Nexus 4 and the cousin LG phone Anandtech saw some discrepancies in the benchmarks results that they eventually traced to thermal throttling. On one phone they had to run the benchmark is several goes due to software issues, and it had better results than on the phone where the benchmarks all run in one go. The only difference was due to cooling between tests on the first phone. To prove the point and avoid the effect they benchmarked both phones in a zip bag in a freezer :-P

Just as for PC chips we'll still see some incremental improvements with new processes and tweaks, but I expect this mobile next gen to be able to last for a while.

I don't think so (but I'm not in this business either, so this is just my opinion).

These ARM servers are not for the general public. A lot of servers now go to the Facebook, Google and Amazons. These guys run their own stacks based on open source, so are not much tied to any ISA. Linux based software run fine on ARM. And they have a lot of loads that are I/O bounds (network mostly), so no need for huge CPU. And costs are critical, both in term of cost of hardware and power consumption (direct and cooling) as the services are often free. ARM is well know for its power efficiency, and the prices and margins are much lower than what Intel is used too.

These companies are the targets for ARM servers in a first step IMHO. Some already have expressed interest so it's not science fiction there: Facebook has join Linaro server workgroup recently for example. Once you have a foot there, you can scale later on to other markets. I don't expect ARM servers to go head to head with Intel in single thread performance for a long while, but I don't think they need to have good business either.

Everybody says that, but it's only true for the high performance / high power consumption process variant. It's not true for the lower power variant(s), which have some differences and are more tricky than the high perf ones (I'm not an expert on this but one issue for example is that LP needs larger wires to reduce resistance and power consumption. This requires in turn more precision to avoid shorts between wires. People who know more on this topic, please share. It's important to understand how the race can turn in the low power area). For low power Atom chips Intel is right now on 32 nm, while TSMC has been on 28 nm for a while now. It's a one year and half-node advantage for TSMC clients. And Samsung is also now on 32 nm (par). Intel announced they will speed up the availability of new finer processes for low power in the future, but based on their respective announcements Intel and TSMC would be on par for LP (we'll have to see how this turns out in practice...). This means that ARM clients can have a competitive process in the low power space today, and possibly tomorrow. It's likely that ARM clients would focus on many cores / low power servers for I/O bounds loads. They can be competitive there, and gain a foothold. Going to higher single thread performance can come later, it would be hard to attack Intel there in the short / medium term anyway. If you pick a fight, pick one you can win. And the ARM world has more experience in LP.

Yes, but where this matters Robust Header Compression (ROHC, RFC 3095. See also wikipedia) will be used so the IP header overhead is not a problem. And where it matters is over the radio link itself, where capacity is the most constrained. ROHC will reduce the IP/UDP/RTP headers to 1 byte typically. VoLTE (Voice over LTE) requires supporting ROHC in the LTE modem for example.

Actually this does exist. Wacom makes exactly such products (for a steep price). But it's a niche product, and a niche usage. For the discussion here they only care about mass volume opportunities. If it's small volume, however useful to some, it doesn't exist here.

It applies to convertible tablets, that can be used as a laptop with a keyboard (the cover type of the Surface, or any detachable keyboard really). It's not only for the Surface but could also be said for some Android tablet with detachable keyboards. I made a similar comparison, but with a seaplane not a futuristic car. It's not a good plane, it's not a good boat, but it has its uses. But it's not mainstream. So here's my very personal point of view.

I used to think that such hybrid devices would be perfect. Get a tablet and a laptop in the same device, so cool. I changed my mind. The reason is that it's either too small (for my taste) as a laptop, or too big as a tablet. And as a laptop the balance is all wrong: to have a stable laptop you want a light screen part and the weight on the bottom part, so it can easily rest on any surface and be stable. A convertible tablet has too much weight in the screen. So you need to put them on a table to be stable, which is less convenient. It's a tabletop not a laptop ;)

In the end I much prefer a true light laptop with a true light tablet (7" for me, I don't agree with Apple on that). Combined it's both lighter than my previous laptop, so no big deal. And they're better for their dedicated use-cases: the tablet as a simple "potato couch" / consuming device, the laptop for productive work. Plus I've no problem giving the small and cheap tablet to the kids, and I can to use the laptop in parallel. As for having separate devices, it's really no big deal. There are tons of ways to sync information across devices conveniently. And having different OS on both devices is a non issue too.

But really, to each his own here. It's more a matter of taste and priorities than anything. If you really need a single device for any reason, then why not a convertible tablet. Just like a seaplane, there will be use-cases where it's best. I don't know if my tastes are mainstream here or not on that topic, we'll see. But if the majority think like this I don't see much future for convertible tablets in the consumer space (actually, did many people bought the external keyboard for the Asus convertible for example? I'm not sure). Maybe for the professional space, for some applications (input while on the go, ...). But it's not the same volume at all.

N*(N+1)/2

Write the same sum but in the other direction just below the previous one, and sum both lines term by term. Notice you have N times N+1, and that's for twice the sum. So one half for a single line. A visual way to let a kid old enough to know multiplication tables to find it for small cases is to draw the sum as dots on a piece of grid paper as a rectangular triangle. Then double the triangle (symmetry on the long edge) and you get a rectangle where the number of dots can be computed with a simple multiplication.

The antenna gain do have an impact on the power consumption. In the transmit side the device power is controlled by the base station to reach a given level at the BS receiver. For a given channel condition a phone with better antenna gain will need to transmit at a lower power than another with a poor antenna to reach the same radiated power, and received power at the BS. So the transmit power amplifier (PA) gain will have to be bigger to compensate for a poor antenna, and the power consumption increase with it. At high gain, a few dB of output can make a big difference.

On the receive path power consumption is not an issue. But the system sensitivity will depend on the antenna gain too. With a better antenna you will receive a higher signal level, all other things being equal. That translates to less drop calls, or higher throughput.

I haven't read TFA (this is /. after all), but yes antenna designs if VERY important in devices. And it's particularly challenging in smartphones, where there are many of them to fit. It's galling to fight on the cellular modem side to scrap tenth of dBs, to see the waste in some antenna designs. But I can sympathize too, it's a too problem when you have so many antennas in a small form factor.

There is a minimum noise floor level in any system (thermal noise). This puts a lower bound on the useful sensitivity as there no point in going much under this floor. And current implementations are very close. So here again, we have a close physical boundary that limits possible gains.

You should take this Intel announcement with a big handful of salt. Intel doesn't make the waver producing machinery, they get it from companies like ASML.

Now, there's been a big struggle between companies like Intel that wanted 450mm earlier, and the tool makers who sank a lot of money on the move to 300mm before and don't want to be burned again in the move to 450mm. The Intel announcement above was to put pressure on the tools providers. It didn't worked out in the end.

All this got sorted out between big boys recently, with Intel, TSMC and Samsung investing a lot of money in ASML to speed-up the availability of 450mm. But the accelerated roadmap has nothing to do with the announcement you quote, just look at it from ASML direct (slide 14). The 450mm process development tools are worked on starting mid-2015 and production equipment is available beginning of 2018. Exactly what is said in the TFA.

450mm is important as it is the only known step that will bring the cost of chips down. Other planned changes (finer processes, 3D chips...) increase performance but also cost. But 450mm requires huge upfront investments, so you need large volumes to recoup it and it will require a big upfront spending. Which is why a lot of people are pushing back. Intel has both high volumes, high margins and deep pockets so they're the most eager to get started. But as you can see, even with their backing it's not that simple and fast.

In a professional context Debian is a perfectly fine workstation desktop distribution. With the longer cycles and better linux support of professional hardware I've never seen big issues, except maybe using a newer kernel for a brand new model. Which is no big deal to handle in a professional context. I've seen Debian deployed on hundreds of workstations with no problem.

Even for home use I stick to Debian. Yes, the out of the box support is not as good as a recent Ubuntu. But the stock stable is usually ok to start (with some limitations). Then grabbing a more recent kernel from backport, or maybe testing/unstable, was always enough to have perfect support in my limited experience.
And then I can benefit from a very stable distribution, where the package maintainers have a personal interest in their own packages. And from my admittedly limited experience outside Debian this makes a difference. I've been frustrated with some commercial distros I tried long ago with some packages that were half-broken. I'd rather have to fiddle a bit at first, but then be able to depend on good packages than having a nice install with bad surprises later on.
That's not applicable to all, and to each their own, but if you are a bit linux savvy you may want to try it.

As a side note, I've recently I've seen people lamenting the lack of stability on linux compared to other OSs (can't remember if it was /. or HN...). They always compared fast moving linux distros to slowly moving other OSs. Well, if you want stability with linux pick a slow moving linux distro! For professional use I've found you don't need a bleeding edge distro, and neither for personal use as far as I'm concerned. Every person will likely need a few different bleeding edge tools for sure, but that's easy to handle (backport, side installs...).

Do you (or anyone here) know about the power consumption when the transistor switches and how it compares to a silicon transistor? Today on silicon the frequency is often limited by power consumption / thermal considerations. In other words, we know how to go faster on silicon but we don't. If graphene is faster but not more power efficient, then it could limit it's use to the few applications where power / thermal are not a constraint. If it's more efficient, but not much, that could also limit the speed gain (power increases linearly with the frequency). So it seems the power efficiency is key, but I haven't seen anything about that (not that I've searched either, but at least I've RTFA ;).

I'm not sure that MIPS is so well placed in the high-end. Yes, they've been high end a long time ago and have had 64 bits support for ages. But today it's a different game, they provide embedded IP now. And where ARM can help their customers optimizing the implementation for a given process (ARM gains this experience by making hard macros and working closely with TSMC, GlobalFoundries...), MIPS has much less resource and just do soft macros. Then up to you to do the optimization. In other words, if you go ARM for an embedded high-performance SoC IP you can leverage a lot of work that ARM does, that you will have to do with MIPS. To get an implementation that is less common in the end.

So the high end may be tough for MIPS. But in the medium end, where price is critical and performance less so, they can be an interesting choice.