Just thought you guys should know that upon upgrading, THIS option (I determined this after a lot of trial and error, since I never had this issue with any of the previous SEP editions), which can be found in the Network Threat Protection settings, will slow down certain websites (Facebook, Gmail, AOL Mail). It also does not allow Speed Tests to calculate your UPLOAD speed (Download works fine). Very strange. And yes, it does it with multiple web browsers. I am using Windows 7 x64.
I confirmed it multiple times by toggling it on and off, re-installing old versions and keeping the option enabled, and manually turning every option under Network Threat Protection on/off until I figured out which particular option was causing my slowdown ever since upgrading.
Thought you guys might want to look into this, since using that option never gave me a performance issue in the past.