The Exchange 2010 SP2 has been announced for the second half of calendar year 2011 !

Here is a list of the new feautres and capabilities that will include:

• 1. Outlook Web App (OWA) Mini: A browse-only version of OWA designed for low bandwidth and resolution devices. Based on the existing Exchange 2010 SP1 OWA infrastructure, this feature provides a simple text based interface to navigate the user’s mailbox and access to the global address list from a plurality of mobile devices.

2. Cross-Site Silent Redirection for Outlook Web App: With Service Pack 2, you will have the ability to enable silent redirection when CAS must redirect an OWA request to CAS infrastructure located in another Active Directory site.  Silent redirection can also provide a single sign-on experience when Forms-Based
Authentication is used.

• 3. Hybrid Configuration Wizard: Organizations can choose to deploy a hybrid scenario where some mailboxes are on-premises and some are in Exchange Online with Microsoft Office 365. Hybrid deployments may be needed for migrations taking place over weeks, months or indefinite timeframes. This wizard helps
  simplify the configuration of Exchange sharing features, like: calendar and free/busy sharing, secure mailflow, mailbox moves, as well as online archive.

• 4. Address Book Policies: Allows organizations to segment their address books into smaller scoped subsets of users providing a more refined user experience than the previous manual configuration approach. We also blogged about this new feature recently in GAL Segmentation, Exchange Server 2010 and Address Book Policies.

• 5. Customer Requested Fixes: All fixes contained within update rollups released prior to Service Pack 2 will also be contained within SP2. Details of our regular Exchange 2010 release rhythm can be found inExchange 2010 Servicing.