Well, we need some generic standard for push notifications first, and we need that standard to not require a centralized server - which kills it right away, since e.g. both Apple and Microsoft insist on people using its servers for all notifications on iOS, Win8 and WP8. Unfortunately, this whole battery optimization business resulted in a kind of lock-in for the new generation of high-level networking protocols.
Why not just sell them into slavery while you're at it?
Lead is trivially cast into bullets.
Black gunpowder is not hard to make, and, for all its disadvantages, can be used quite successfully in single-shot or manual-cycling designs (bolt/pump/lever-action), and even some repeaters (e.g. DAO revolvers).
Cases can be made out of plastic - see shotgun shells.
This leaves the primers. I don't know if these can conceivably be home-made, but I suspect it's not all that hard.
Anybody can create a gun out of a bunch of metal pipes and a couple of springs, all readily available in the local Home Depot, with as little as an electric drill. This has been true for decades now, too. It's just as untraceable, and you can actually make semi-auto (or even full-auto) weapons firing a decent-sized round that way. So, nothing new here, other than all the sudden attention.
The "future" has been here for a long time now. It's just that the media shit storm has caused more people to suddenly notice.
It's all about the rifling or lack thereof, not about the caliber. A rifled 12 ga slug gun is legally a rifle (and would be a destructive device if 12 ga wasn't specifically exempt as "suitable for sporting purposes", or some such).
They do say that Win8 Metro apps will be trivially portable. I can't help but wonder if that'll include games. For a lot of indie stuff, this would be quite sufficient.
There's no need to replace XMPP with anything, it's good enough. It's getting the big players to support it that's a challenge. A different standard would face the same exact problem.
The problem, as I understand it, is that iOS background model for apps is not conductive to pre-existing protocols like XMPP. For networking, if you want to react while in background, you have to use Apple's push notification service. On the other hand, for a compliant XMPP client, you have to keep a network socket to the server open at all times. All iOS XMPP clients that I've seen connect to app developer's server instead, which serves as a gateway; but, of course, this means that you are handing your credentials to the middle man, and they can spy on your communication if they want to.
Apple does allow apps to keep a background socket open indefinitely if they declare themselves as "VoIP", but they do actually check whether the app uses this capability for its intended purpose. I believe an XMPP client would only qualify if it's using the socket in question for voice traffic; it still can't use it for text.
GTalk did not allow for inline images either, until Hangouts. Formatting is not that big of a deal, I think.
I mean, at my work, my group all ran out and got google accounts, even the Apple users, because gtalk worked everywhere and Office Communicator did not. Now, gtalk does *not* work everywhere, and now we have to rethink that.
GTalk/Hangout actually now works on more platforms than before, in an officially supported way, since they've added an iOS client; and the web one can handle all desktop platforms. The problem, rather, is that you can't pick the client that you want anymore; you can only use what Google tells you to use.
In terms of platform portability, though, I have found Skype to be very handy lately. Proper rich clients on all desktop OSes (including Linux, even!), and on all major mobile OSes as well. And, ironically, the only platform where it works poorly is Windows Phone 8.
But, of course, it's still a closed source app with a proprietary closed protocol.
I explained Google's line of thinking. Nowhere did I say that I approve of it or personally like it.
On the other hand, it never had a decent iOS client, and now it does. And their web client also works as a separate app if you have Chrome...
Don't get me wrong, I personally hate these changes also. But I think that we don't really make the majority of people, and Google is firmly in the "go for the bigger crowd" camp now, along with all other major tech companies.
If the majority of your GTalk contact list are people from other XMPP/Jabber servers, you're in a tiny minority of overall users.
Most people using GTalk these days are doing so because it came on their Android phone, and they needed a Google account to buy apps. Most of their contacts are in the same boat. They may not be aware that this Google account they have is also a G+ account, and that's precisely what Google is pushing for here - notice that one of the features Hangout adds is the ability to send freshly snapped photos, and the way it does it is by means of a G+ photo album...
These are all relative. A mental scale of someone living in Novosibirsk (where kids go to school so long as it's above -25 C) is probably different from the one of someone in LA.