The SQL Server 2008 SP2 has major improvements that include integration of reporting services with SharePoint products and several management improvements. This final version of the Service Pack 2 includes new compatibility features with SQL Server 2008 R2 and hotfix solutions provided in SQL Server 2008 SP1 Cumulative Updates 1 thru 8. For example, with SP2 applied, an instance of the SQL Server 2008 Database Engine can be enrolled with a SQL Server 2008 R2 Utility Control Point as a managed instance of SQL Server.
You can read all about new features and enhancements in the Release Notes.
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