As you can see there are a lot of fixes in this rollup, I particularly worked in many issues involving 2501650 and 2502686 while the hotfixes were not even ready. Due the nature of those issues I strong recommend you to download this update and plan the installation on your Forefront TMG. To install this update, you must have TMG 2010 SP1 and Update 1 already installed.
Go get it at http://support.microsoft.com/kb/2498770
Download At Source