They are one of those risky companies to work with. Even their terms and conditions are slightly ambiguous to me:
http://www.activision.com/legal/terms-of-use my interpretation is that you can upload videos as it falls under UGC (User Generated Content) but can't monetise. But that's just
my interpretation. You'd be much safer requesting permission from them. The thing is, I still don't know whether some publishers define YouTube's partnership as commercial use or not.
There's also this part:
"You may not copy (except as expressly permitted by this license and any other applicable terms, conditions, or usage rules), decompile, reverse engineer, disassemble, attempt to derive the source code of, modify,
or create derivative works of the Product, any updates, or any part thereof (except as and only to the extent any foregoing restriction is prohibited by applicable law or to the extent as may be permitted by the licensing terms governing use of any open sourced components included with the licensed application)."
I want to do let's plays of CoD games at somepoint someday but at this stage Activision just don't seem let's play friendly in my eyes.