I'm using IE7 with no problems. I like the tabbed browsing, even if it's an idea they stole from Firefox. The previous version of Firefox was getting quirky for me, so I decided to try IE7. I'll probably go back to Firefox when I get a new computer with sufficent hard drive space for two browsers. Space is really at a premium for me now, and I've removed everything I can from my C:/ drive.
One XP update - I think it was Service Pack 2 - left a lot of backup stuff on my C:/ drive, and I can't delete it and can't figure out why I can't.
-Joe-