Today, at Max 2007, Adobe has announced availability and the list of new features of  the second public beta release of Flex 3 SDK and Flex Builder 3. Below is a quote of this announcement:

"Check out these important new features in Flex 3 beta 2:

• New wizard support for .NET
  New wizards for auto generating applications
• Web service introspection
  Introspect WSDL files and automatically generate connection code for invoking web services
• Major improvements to performance and memory profilers
  Investigate memory usage and analyze where your application is spending its time

In addition, you'll want to check out the new

• Flex Skin Design Extensions
  Quickly and easily export Flex skins from Adobe Photoshop®, Fireworks®, Illustrator® and Flash®

And, of course, you can test these and other great features:

• Support for Adobe Integrated Runtime (AIR)
  Extend Flex applications to the desktop
• SWF size reduction
  Reduce file size by caching the Flex framework on users' computers
• Refactoring
  Find and rename references to classes, variables, and methods
• Ease of integration with Adobe Flash CS3
  Use your interactive, animated content from Flash as a component in Flex

Flex 3 beta 2 is near feature-complete and is a very high quality beta release."