I wonder, have all the XP voters actually tried running Windows 7?
I have been running Windows 7 since it's beta stage, then I got the full version for free. I had previously been running windows Vista Ultimate since it's beta which I later bought for somewhere in the 3 figure range of Her Majesty the Queen's sovereign pounds. (or something).
Anyway, I tried running XP lately and I found myself lacking a huge amount of features I have come to be extremely fond of.
Things as simple as window snap, which you can't live without as a programmer on a widescreen in order to have two windows up at once as fast as possible.
The "Breadcrumbs" in the address bar allowing you to click and go instantly to any folder.
Libraries which I can drag folders I use regularly to in order to allow me to open them instantly from any explorer window with only 1 click, and when you're working on 3 or 4 projects simultaniously as I am and time is so critical, these little perks really save you some time.
I admit I still don't unnderstand the purpose of Desktop Peek.
Performance wise, no equivalent operating system I have ran will even touch this Windows 7 x64 build I am running, I have to use Linux regularly for which I have become fond of Ubuntu recently (I used to be a fedora fan, but I don't have the time to mess around setting up hardware that doesn't work like I used to) and Ubuntu just gets it done.
I do find myself perpetually coming back to Windows, aside from some of the important every day development tools I require only being available in Windows flavours, sometimes I just need things to run smooth and simple the way I'm used to and have come to expect since using 7.
Aside from that, my second favourite OS has to be android for mobile devices, but that's a whole different story, and very deserving of a Universe of it's own let alone a thread.