The CRM 2011 Update Rollup 13 (UR13) release is now available on the Download Center at http://www.microsoft.com/en-us/download/details.aspx?id=37133. UR13 will be available on Microsoft Update on April 9th.
The CRM 2011 Update Rollup 13 release adds support for Windows Server 2012. Upgrade instructions can be found here: http://technet.microsoft.com/en-us/library/dn167638.aspx. To install CRM 2011 on Windows Server 2012, a setup update is also required. Thus, it is necessary to wait for availability on Microsoft Update. The CRM 2011 Report Authoring Extension component has been updated to support SQL Server Data Tools and Visual Studio 2010. More information can be found at http://www.microsoft.com/en-us/download/details.aspx?id=27823. The release also contains a set of fixes to address customer issues.