SQL Server 2008 R2 Service Pack 1(SP1) Customer Technology Preview (CTP) is now available for download. SQL Server 2008 R2 service packs are cumulative updates and upgrade all service levels of SQL Server 2008 R2 to SP1 CTP. This service pack contains the cumulative updates up to SQL Server 2008 R2 SP1 cumulative update packages 6.
What’s New in SQL Server 2008 R2 Service Pack 1
For a detailed list of new features and improvements that are included in SQL Server 2008 R2 SP1, review the What's New Section in Release Notes.
Please note: This Customer Technical Preview (CTP) release is not supported by Microsoft Customer Support Services. Please submit feedback using the Microsoft SQL Server Connect Feedback Center. In addition, some of the fixes documented in this CTP release may not be included in the final release. There may also be fixes included in this CTP release that are not documented in the master KB article.
Taken from <http://www.microsoft.com/downloads/en/details.aspx?FamilyID=bd200f8e-ba8a-45e3-af59-e28a9e2d17df>