First impressions:
1. Faaast!
2. 78/100 on Acid3 Test
3. Tabs work great
4. Bookmarks are easy to maintain and move around
5. Gears is installed by default - works great with Wordpress
6. Haven't seen a site that doesn't render correctly -- even those heavy in Ajax
7. Flash sites run well
8. Silverlight not yet compatible
9. Mobile Me works