The Flash Player 10.1 and AIR 2.0 Public betas are now available via Adobe Labs:
These are the first fruits to come out of the Open Screen Project – and hopefully much more good will follow as FP 10.1 for mobile devices will begin shipping later this year into next covering mobile platforms like Palm, Blackberry, and Android.
Some good resources:
Flash Player 10.1 Beta Release Notes
Introducing Adobe AIR 2 beta
Flash Player 10.1 public prerelease demos and interviews
Mobile and digital home
UPDATE: Wow. Christian Cantrell has everything you could need at AIR 2 Public Beta Resources.