As Steve mentioned below (http://blogs.technet.com/windowsmobile4partners/archive/2005/08/16/409294.aspx), we should be see the Community Tech Preview in the very near future. If you are anything like me, you'll be saying "well the feature list looks great, but what does it actually do and how does it work?". If you want to find out more about how the new functionality hangs together check out these posts on the Exchange team blog:

Solving the Phone Synchronization Problem End-to-End (http://209.34.241.68/exchange/archive/2005/06/07/406035.aspx)

Exchange 2003 Service Pack 2 (SP2) Remote Wipe functionality (http://blogs.technet.com/exchange/archive/2005/07/07/407416.aspx)

Enforcing security settings on mobile devices with Exchange 2003 SP2 (http://blogs.technet.com/exchange/archive/2005/06/20/406586.aspx)

One really interesting snippet hidden away in last paragraph of the third article is that the security policies that you can now apply are available at the mailbox level. The Exchange System Manager only gives the ability to set these at a global scope, but using scripting or ADSI calls you could set differing policies on individual mailboxes. I smell an opportunity here. If anyone has the time to knock up a GUI tool to enable administrators to manage this effectively I am sure there will be a lot of demand from enterprises for it and I will certainly be interesting in hearing from you!