Today, Exchange Server 2010 SP1(Service Pack 1) is released.  The download is here: Microsoft Exchange Server 2010 Service Pack 1 (SP1). Here you have an overview of the things that are new in Exchange Server 2010 Service Pack 1 (SP1): What’s New in Exchange 2010 SP1. For information about known issues with Exchange 2010 SP1, see Release Notes for Exchange Server 2010 SP1.