I think you may be missing the point.
I don't want to buy a new OS. I don't want to give Microsoft money for a OS that I don't want to use and am locked into because one software package I use is Windows-only. I certainly don't want to be forced to get new hardware in order to pay money for something I don't want to use.
While my CPU and GPU aren't breaking any records (Intel Q9550, GeForce 9400GT) and I may have other minor issues, I'm also not feeling any need to upgrade. I don't do high end games, my primary OS is a Linux flavor, my compiler works fine for my development work, and except for when an application goes rogue and eats CPU or RAM, my 4 VMs run fine with 4G Ram. One of those VMs is Windows (XP 64bit), running on a license I happened to get with my hardware. I use the windows VM for 2 reasons -- one, for a decent OCR package, and two, one of the media servers I use is a Windows-only package.
If these ran well under WINE, I'd ditch windows in a heart beat
Would I like to be using Windows 7 rather than XP? Sure. If a license fell into my lap, I'd upgrade. However, I look at my windows partition in much the same way I look at dental work -- of course, I would rather getting Novocaine before dental surgery, it is a nicer option than not, but I'd rather not have to have dental work in the first place.
 - In particular, I'm rather annoyed that while my CPU supports it, the motherboard doesn't do VT-d,
 - I spent over 2 months trying to train Tesseract and Cuneiform to a workable state. I re-wrote significant parts of a UI front-end to make them play nice together and to select the best recognition from either engine. Best I could get was a recognition accuracy on my bank statements of 75% by _character_, much less word or line. And there still isn't an reasonable way to do document formatting replication in the recognized text.
 Yes, yes, I use closed-source software. I am a Bad Geek. Can we please move on?