With the release of these 2 technologies (Flex 3 and AIR 1.0) there were also web pages and sites that are online now. One of the most exciting of these sites is OpenSource Adobe (http://opensource.adobe.com). In this web site you can find the technologies that Adobe is contributing to and also the technologies you can contribute. In their own words

This site presents the definitive view into open source activities at Adobe

For example technologies like Flex 3 and also Flex 4 codename Gumbo (comming soon), Blaze DS, Tamarin Project in collaboration with Mozilla Foundation, WebKit and more.
In this site there is documentation about the technologies, some source files of the techs, there is a forum and samples.

The three main technologies shown by the site are Adobe Flex , BlazeDS and Tamarin Project.

Best Regards.