I've just installed SQL Server 2008 (not R2) and applied SP1 and then found this link.
http://support.microsoft.com/kb/2814783
Cumulative Update Package #10 for SQL Server 2008 Service Pack 3
Should I install this to bring SQL2008 up to date with the latest service pack and cumulative hot fixes or just leave it at SP1? I can't tell you if we're having any of the problems the hotfixes resolve. I'm going with the "this is the latest service pack so it should be installed" school of thought.