Otherwise I go to http://www.callofduty.com/ click Black Ops 2 from titles in the upper left corner, then click forums on the header bar.
I have the forums bookmarked. I'm currently using the Andriod Dolphin HD browser (Beta version with HTML5 support). Unfortunately the banner at the top of your site doesn't display correctly in this version, hence the bookmark. (I should mention I also have the current Dolphin HD offical version installed and that displays the top banner with the forum link fine, but has issues with interacting with posting to threads, hence using the beta). Sorry for the waffling.
Edit: Ignore this banner works fine in latest version and posting is fine if you're not a numpty and turn off predictive text
Booked marked on Firefox. I also have it favorited on my iPhone.