Google recently published the individual breakout sessions from Google I/O on the Google Developers Youtube Channel. They are publishing the videos and slides of each presentation gradually over the next week.
Here is the release schedule, as indicated on the Google I/O session video page:
Here are some sample videos to get you interested.
A Beginner's Guide to Android (with Reto Meier):
PDF of the "A Beginner's Guide to Android" session is here.
Google Web Toolkit's UI Overhaul:
Google Storage for Developers (For Google App Engine)
PDF of the presentation is here.
The original schedule for developer sessions is here.
For more info, check out the Google Code Blog and the Google I/O Twitter feed.