The 3.0 branch continues to evolve the field of exploitation research and exploitation frameworks in general. The primary goals of the 3.0 branch are listed below:

-Improve automation of exploitation through scripting
-Simplify the process of writing an exploit
-Increase code re-use between exploits
-Improve and generically integrate evasion techniques
-Support automated network discovery and event correlation through recon modules
-Continue to provide a friendly outlet for cutting edge exploitation technology

http://www.metasploit.com/projects/Framework/msf3/

Don