Several reliability fixes included:
http://support.microsoft.com/kb/2689195
To install UR2, you need to be running SP2 (with or without UR1) already.
Did any one have had problems with this Update so far?
I've heard of a recent set of problems caused by something pre-this-update, which applying this update fixed. Not sure beyond that.
Will it come with Microsoft Update or WSUS in Future?