I'm not so sure Google wanted it to be released like this but here you go...
Notables include the Google Talk video chat, the new UI and the integration of Books, Youtube, Gmail and Google's other properties.
The video was briefly posted to YouTube in the Android developers account, then taken down. Android Police then reposted it and Google has yet to pull it from YouTube since the cat is now out of the bag.
Update: Here's the Official Google statement.
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