Edit: Update Rollup 17 is now available for Exchange 2010 SP3 see the post Exchange 2010 SP3 Update Rollup 17 installation tips.
Update Rollup 5 was released for Microsoft Exchange 2010 SP2 on the 13th November, but has since been pulled from the download page due to issues it causes once applied.
The original Microsoft download page can be found here (but currently fails to load):
More information can be found below on the exact issues.
As soon as I have an update on the Rollup availability I’ll let you know.