RC=release candidate=just about done

http://www.microsoft.com/exchange/2010/en/us/try-it.aspx

The key release themes, to help you position to your customers, are as follows:

  • Flexible and Reliable
  • Anywhere Access
  • Protection and Compliance

You can get the product overview here: http://www.microsoft.com/exchange/2010/en/us/overview.aspx