The results are actually quite unimpressive. I think that's a good thing and it reflects the fact that Windows 7 is built as a very solid operating system. They took Vista and "fixed it." That's how I look at Windows 7. It's considered a minor upgrade from Windows Vista, but in my mind it's what Windows Vista should have been.
In any case, I'm testing Windows 7 Service Pack 1 beta and I'm finding no significant problems or issues with it. I'm doing this on a PC that's not a mission-critical computer, so I can afford to load the system to see how I might make it crash.
If you're still running Windows XP on your computers, get ready to lose Microsoft support in 2014. That may not seem too far away, but it feels like it's right around the corner when I think about how quickly 2010 is going by.