An Epic 22-Minute Walkthrough of Windows Phone 7

It's a time commitment, no doubt. But if you REALLY want to know more about Windows Phone 7, MSDN posted a 22-minute tour with Joe Belfiore (VP of Windows Phone Program Management) explaining each of the features.

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If this is a bit too much, you can get a good feel of WP7 in motion here, too. [MSDN]