yeah baby … source: http://www.microsoft.com/exchange/2010/en/us/default.aspx
The public beta of Microsoft Exchange Server 2010, part of Microsoft’s unified communications family, is now available. Exchange 2010 is the first server in a new generation of Microsoft server technology designed and developed to work on-premises and as an online service, and introduces a new integrated e-mail archive and features to reduce costs and improve the user experience.
… it’s a 295mb download …
When will Exchange 2010 be available for purchase (generally available)? In the second half of 2009.