Totally agree. At least Linux has no concept of "default UI" and is thus easy to choose the one that fits you best.
Windows, OTOH, is designed with the notion that you will use the UI provided by Microsoft and is not as easy to change. Add that to the fact that I really don't like the direction Win10 is going and I honestly don't know what I'm going to use once Windows 7 is too old, i.e.: Doesn't play nice with new hardware

You joke but I fear this will come true. After decades of refining the interface for use with a keyboard and mouse we will get "one size fits all" programs which will be equally unsuitable for both desktop and mobile devices. If anything they'll be more tuned for touchscreens since that's where the future seems to be.
Call me a luddite if you want but I think that the desktop oriented and touch oriented interfaces in Windows 8 and 10 should have been kept separated. In the Windows 10 preview some applications have a touchscreen oriented interface and others have a desktop one. In a mobile device you should get only the formers and in my desktop I should get only the latter.

So will I.
All I want from an OS is to work well and to stay out of the way. Windows 7 does just that. Windows 10 doesn't. I hate how they make it difficult to login with a non-Microsoft (local) account. I hate how they've integrated so many Microsoft services.
also, the fact that they're upgrading Windows 7 and 8 users for free speaks volumes about how desperate they're to get everyone in Win 10.

They want you to use their new and wonderful app store of which they'll get a cut of every sale.
They want you to use all the services they've integrated to the OS: OneDrive, Bing, Cortana, etc. so that you might get a subscription for one of them, or giving them your data to mine (the Google model) or that you get so accustomed to the Microsoft ecosystem that you buy one of their phones or tablets.
And I don't like it either since it means that Microsoft it's sure it'll get more money from you on the long run than if you'd paid for the OS upfront. It also means that they'll likely integrate more of their services into the OS à la Google with Android.

Yep. There seems to be (at least officially) no plans yet for a subscription-only Windows, but I believe they will go that route. At least they'll try and see how it goes.
After all, they're doing something similar with Office: They're encouraging everyone to get the subscription version. It's a no brainer, although cheaper initially it'll make Microsoft more money on the long run.
The fact they're esentially giving away Windows 10 strongly suggests they've thought of a way to get more money from us on the long run. And I hate this: I prefer knowing how much money I'm gonna pay upfront

A bleeding edge gaming rig is just a set of very expensive not-much-faster-than-midrange parts. Besides, anything marketed "gaming" is very overpriced. You can get a very decent PC for 2x what the consoles cost. That PC will play 95% of games perfectly. The rest will work ok if you dial the settings a bit. It does does many more things that a console. Also the games are cheaper on PC and in PCs backwards compatibility goes back as far as 30 years. In consoles, if you're lucky you can play the games of the previous generation. Sure, the consoles are cheaper and simpler to use, but my point is that a decent PC is not that expensive.

...Variety of devices, Running different versions of the OS.
The first one IMHO is a strong point for Android since there's so many different devices you're likely to find what you want (cheap, expensive, large, small, metal build, removable battery...). In this respect Windows Phone also has an interesting number of devices (although infenitely less than Android) and iOS is horrible in this respect: You basically have this year's or last year's model, neither of which is exactly cheap.
The second one is definitely bad: Several versions of the OS having significant marketshare means extra work for developers, and fewer apps for users (since some require a version newer than you have). Windows Phone and iOS are much better than Android in this.

You nailed it (except for the developer stuff which personally doesn't bother me). This should be sent to Mozilla's CEO right away

I'm sure the Flame phone is very nice and that Firefox OS works great, but you're talking like all Android phones cost 600$. And you know that's simply not true:
Look at something like the Moto E: A decent phone for less than 100$.
I mean, I have no thing against Firefox OS and I'd love it to see it succeed, but it's simply not true that the hardware it runs on is significantly cheaper than the one of other OS (Android and Windows Phone who has some pretty cheap phones too)

Spot on. Microsoft really want you to get hooked on their services. That's why they're releasing Office apps for iOS and Android, an Android launcher that obviously uses Bing as the default search engine, why they're increasingly tying Windows to Bing, Cortana and OneDrive amongst others.
I don't blame they as that's where it looks the money will come from but I don't like it because I like my software to stand alone and not depend on third party components.
That's why I love Windows 7: I paid once for it and it's a piece of software that does what's supposed to, doesn't try to sell you a millon services and gets out of the way. Compare that to Windows 8 or 10 which for starters, makes hard not to login with a Microsoft account from the moment you install it and depends or tries to sell you many Microsoft services: The Windows Store, Bing, Cortana ... Also, I'd also like Google to let you pay with money, let you use their services with no ads and no spying in exchange for some dollars

I pray to the gods that the Windows UI designers read your comment and decide to undo this madness. Microsoft are determined to have a unified interface between desktop, tablet and phone and will cause the desktop to be less useful and harder to use if necessary.

It enrages me to no end the current trend of using OSs to sell you services: Google did it with Android (understandable since they live off your data, but I'd pay money for an Android which wasn''t tied to Google's services), and now Microsoft is doing it with a desktop OS. The free upgrade during the first year to Win 10 further confirms this: They're desperate for you to move to their data-grabbing, service-selling new OS. I'd rather pay some money and get a clean OS like what Windows was until 7

Anyone catched the quote on the Windows keynote the other day? "We see Windows as a Service". Soon you won't be able to purchase a Windows license, you'll have a recurring subscription. And this way the problem of people not upgrading will be solved forever.

Ain't it sad that to make Windows 8 usable you have to install a third-party program? Microsoft failed hard with Win8, and the worst is that they knew but they HAD to use it to get people used to Windows Phone and to use their services

Many (all?) of the things the Steam client displays are webpages and thus it contains a web browser and those are heavy beats. I believe that's the reason the Steam client uses so much RAM