We have released the Updte Rollup 10 for Exchange Server with Service Pack 3.
You can see all the included improvments at :
Update Rollup 10 for Exchange Server 2010 Service Pack 3
I am including them here for viewers comodity :
If you want to download here's the direct link :
Download Update Rollup 10 For Exchange 2010 SP3 (KB3049853) from Official Microsoft Download Center