Robert McLaws posts about his IE7 on XPSP2 - First Impressions. Hint: he may be a windows fan, but he's not a fan of IE7. Lots of poorly implemented things pointed out. I'ts only a beta of course, but it sounds like some of the key "new" functionality (tabbed browsing, RSS) is either broken or just horribly implemented. Also, why are you still needed to reboot your computer after updating your web browser? Wasn't that gotten rid of ages ago?
<sarcasm>I can understand that you have to reboot when you upgrade your mp3 player, but not your web browser.... </sarcasm>