- Browser performance has improved
- Flash performance has improved
- HTML5 support
- New highlighting of checked items in gmail/mail client
- USB peripheral support (haven't tested)
- Storage broken down into media types (apps/photos/videos/etc) under settings menu
- Hitting "back" in the market goes back to where you were instead of kicking you back to the top of the list which was very annoying
- You can force a check for future OTA updates with a "check now" button
- Camera/Gallery views are MUCH improved - images are sharp and crisp like they should be.
- Resizeable widgets (requires developer to change an attribute in their xml) - Stock gmail/mail/calendar/bookmarks are all resizeable
- DRM support gives us music and movie purchases now, I hope netflix is soon to follow.
I'm sure there's more. A couple things broke but I suspect they'll get fixed right away (paradise island app doesnt work now, boo hoo)
Oh also, the shortcut to your movie editor will probably be broken. After updating... remove the shortcut and re-add it.