Brand new info about Exchange 2010 SP1 on the MSExchangeTeam.com blog:
While we appreciate all the positive feedback we've received on Exchange Server 2010, we know you all are eager to find out what's been going on in Redmond since November. Today, we are happy to give you a first look at what's coming later this year in Exchange Server 2010 Service Pack 1 (SP1).
SP1 will include fixes and tweaks in areas you've helped us identify, including a roll-up of the roll-ups we've released to date. I also wanted to flag some of the feature enhancements we're excited to bring to you with SP1 including: archiving and discovery enhancements, Outlook Web App (OWA) improvements, mobile user and management improvements, and some highly sought after additional UI for management tasks. This is not an all-inclusive list, so stay tuned for the detailed list coming soon!
In addition to sharing these details with you, I'm pleased to let you know that we'll be offering a beta of SP1 for download in parallel with TechEd North America this June. This will give you a chance to test drive SP1 and prepare for its official release.