The Exchange 2010 Beta was released just the other day.  I encourage everyone to read more about all the new features and improvements that we've made here:
http://www.microsoft.com/exchange/2010/en/us/default.aspx

Just some of the cool new features:

  • No more Storage Groups
  • No more LCR/CCR/SCR
  • New, simplified high availability with Database Availability Groups
  • All new Outlook Web Access, and integration with OCS
  • and a whole lot more!

You can download a copy of the beta here and give it a try in your lab:
http://www.microsoft.com/downloads/details.aspx?displaylang=en&FamilyID=1898ed2c-2f88-48ac-824e-d3d20fad77d7