Well, I decided to suck it up and buy Windows 7. I'm using it right now.
I'm actually very glad I did. I did a fresh install, and it's running faster out of the box than Windows Vista did after I optimized it for speed. Although that could be for several reasons:
1. I got the 64-bit version of Windows 7, whereas my Dad had forced me to take the 32-bit version of Vista (I wanted 64-bit, he told me it would break all the plug-ins and any older applications, but when I installed it, it didn't).
2. I have a quad-core processor, which benefits from the new way Windows 7 handles multiple cores.
3. Windows 7 no longer does double-buffering and software-rendering of graphics.
On top of that, I really like the fact that the date shows up on the taskbar now, and the fact that I can now use Aero with almost no performance penalties, where as under Vista, my system ran 10% slower if I enabled Aero. I also love the new unit conversions in the Calculator. No more Google searches for Celsius to Fahreinheit converters!
So, I guess I was wrong. There ARE enough new features in Win7 to justify the price tag. Just barely, but there are.
On top of that, I've noticed that my 3D games are far more stable. The whole system is more stable.
So, to anyone who's suffering with Vista... I can confirm you're better off either downgrading or upgrading. This is much better than Vista.