DubConqueror: Clouds are for documents what online DRM is for games: making one too dependent on external parties for things that are basically mine only.
Oops, I did it again... skip the fearsome wall of text if you hate these.
TL:DR - cloud storage is typically both local and cloud with local synced to cloud. You are not dependent on the cloud to get at your data. It is not like DRM. In part 2, I actually toss in my views about the topic at hand here.
About the cloud for anybody not already knowing this: I know you posted this some time ago but it made me wonder if you and possibly others are aware of how personal cloud storage tends to normally work with the major players such as Google Drive, Microsoft's Skydrive, Apple's iCloud and the most popular of them all (and the most flexible I might add) Dropbox.
The way these services operate by default is to maintain all of your data both locally and in the cloud. The idea being that should you be offline you still have complete access to all your files. Once you go back online again whenever that is, changes are synced up to the cloud at that time.
Of course, there's exceptions to every rule such as online applications which read and write data in the cloud like Google Docs. While they can save stuff locally on demand the default behavior is to do nothing locally with you data. I wonder how much that stuff really gets serious use aside of Chromebook users.
So, they just possess a copy of your data and the benefit of that is off-site storage of valuable files more than anything. For example, photos, rare music ripped from CDs that would be hard to find or expensive if you could, movies you've made, etc., etc.
If anything, a lack of flexibility with some of these services is a problem when you want to offload data that is local and just keep in the cloud to save space on your primary drive where these services tend to store data locally. Dropbox is the most flexible I have seen in looking into the options in that it allows me to pick and choose what folders sync and what folders do not. So, I could upload a bunch of archival stuff without it wasting space on my startup disk. It's nice to have that option.
Don't get me wrong. I do not have complete faith in the cloud anymore than I do in any other storage system. I keep data like that locally on an external USB drive. In some case redundantly on a second one for precious data like family photos and my music library just in case the external drive bites the dust.
I see cloud storage as a good thing in that somebody could break into my home and steal my computer and the external drive next to it and even the one in the closet and I'd be screwed. Similarly a house fire would likely destroy these things and if I lived myself I'd be pretty sad about that. If the stuff is in the cloud too, I am safe from unexpected disaster of pretty much any kind. Cloud storage for the important stuff has become cheap too.
So, nobody is getting your data in a DRM sort of way where they are controlling access to your stuff. Quite the contrary, you control that unless they have a devastating problem on their end and lose it all. Barring natural disasters that isn't too likely though as I am sure they redundantly back up as well.
We now return to the original topic: As for Microsoft wanting an online account to login to your operating system every time you use the computer, I don't think that's happening. It'll be optional is my guess although they probably will require it one time as a DRM thing to tie that account and license to your hardware in oem license fashion as has been mentioned elsewhere not to mention setting you up whether you like it or not to access their app store. I really cannot imagine an online login requirement to use Windows regularly though. That just isn't going to fly with users.
On my Mac I have an AppleID account to access all things iTunes from the Mac App Store to music, movie rentals for my AppleTV box, etc., etc. They also bill that same account for cloud storage I opted into. However, I do not need that account at all to login to OS X. I have a entirely separate user account for that. I think after a one time registration and account creation during install that will be what most Windows users wind up with as well but knowing Microsoft it may not be the default. I suspect users will have to deliberately set that up themselves. That's just my guess.
I have zero interest in Windows 10 personally. I run XP and Win7 in virtual machines using a software called Parallels that has built in DirectX support and works very well for many titles although obviously there is a performance trade off there. It's one I've found easy to live with however. I'm phasing out Windows here as I play the stuff I own that requires it. I'll hang on to the XP VM for as long as I can get away with it for GOG classics, etc. but whenever my two Windows licenses become obsolete I'm so done with them. They can't even give it to me for free. Fortunately, a lot of GOG titles run very nicely in Boxer (DOSBox for Mac) and Wineskin (A nice Wine setup app for Mac) so even if I tossed Parallels I'd have most of my oldies but goodies to play.
Mac gaming is a lot better than people who don't do it might imagine. For everything else, there are Playstations. Say what you might about Apple but they don't screw you around like Microsoft does in my experience. I didn't get to be a fanboy without being given reason to be.
There's never been a better time to start looking at alternatives and I don't mean just my personal favorite. If I didn't have this Mac I'd be looking real hard at what my favorite distro of Linux could be. I've run Linux quite a bit in the past. I like SuSE myself but Mint is nice too. I'm a KDE fan personally or at least I was then. I'd have to re-evaluate that after this much time. I tried Ubuntu but I hated Unity. Of course, you aren't forced to use Unity. Fedora didn't do it for me either. Gentoo tempted me but I was too lazy. The wonderful thing about Linux though is there is just so much choice. Like with OS X, gaming on Linux has come a long way in recent years. A combination of an alternative OS and your favorite console and you too can be Microsoft free! Well, that assumes your favorite console isn't an Xbone.