The new Flex 3 and AIR betas are available on labs this is the last public beta releases, the new betas resolve various bugs from beta 2, so if you haven’t already give it a try.
Here’s The info on Adobe Labs:
This final beta release focuses on overall quality and performance, providing a final look at Flex Builder 3 prior to launch. Please use this opportunity to further explore the new features, communicate any final feedback, and test your existing Flex applications using the Flex 3 framework.
This download provides the beta 3 version of Adobe AIR. This runtime is required to run any Adobe AIR application. The Adobe AIR beta 3 was released on December 12, 2007 and contains a timeout that will cause it to stop working on November 1, 2008.