Microsoft has releases the new CTP of the MS SQL Server 2008 R2, here is the download page to Download November CTP of the MS SQL Server 2008 R2 http://www.microsoft.com/sqlserver/2008/en/us/R2Downloads.aspx
Find the information on the System Requirement here >http://msdn.microsoft.com/en-us/library/ms143506(SQL.105).aspx
More information about the SQL Server 2008 November CTP >http://www.microsoft.com/sqlserver/2008/en/us/R2.aspx
