Exchange Server 2010 beta was released to the public this week.  The beta for EWS managed client API has also been released.

Check it out the related blog posts:

Presenting Exchange Server 2010

http://msexchangeteam.com/archive/2009/04/14/451032.aspx

Introducing the EWS Managed API

 http://blogs.msdn.com/exchangedev/archive/2009/04/15/introducing-the-ews-managed-api.aspx

This is especially exciting for me because I am currently working as the beta support engineer for developer support.  What that means is that I am support customers who are working with Exchange Server 2010.  I hope to post some content here about what's available to developers in Exchange Server 2010.