Google Instant available in labs
Much more stable
HTML5 Videos can be played
'Downloads' open as a popup, not fullscreen
New crop interface when setting a wallpaper
Picasa albums can be 'pinned'/made available offline
New Emotion pictures in chat
Applications now show as being installed when browsing
Now remembers position when searching through apps
Different colour text selector handle
Long-press accessibility options
Upload/Download Indicators on the WiFi status icon
If you have your Xoom 3g in Airplane mode with wifi on it remembers after reboot.
When you click System Updates, you can now click, 'Check now' for updates
New Debug icon in notification area
The appointment dismiss dialog box is now small and is not covered up by the notification balloon.
"Lock Screen Orientation" changed to "Auto-rotate Screen"
Now says "Shop" at top right of app drawer, instead of just an icon
Icon glows, either side of the current apps page in the drawer, are now fixed
New "Videos" application
Playback controls are now along the bottom and can be used while buffering
HQ option now renamed to HD