I don't know what kind of AA CloD uses natively. But it was my understanding that the 'hacky' aa that a user found on the Arma forums and which works with CloD, is FXAA, apparently similar to MLAA (ie, is nVidias answer to ATIs morphological aa).
FXAA works nicely imo with CloD, but not the ingame aa that is possible with CloD currently (ok, it 'kinda' worksi, but the purpose of aa is to smooth out the jaggies, so if you're still seeing these artifacts ingame then the job is not really being done).
There are so many types of aa these days it's almost a pain. Anyone who's played FSX probably has fallen in love with supersampling aa because it really smooths out the whole image beautifully and eliminates bad shimmering, which the other aa's don't. It's always subjective but I always felt that this kind of aa made a world of difference.
Take your pick! hehe
CFAA
CSAA
FXAA
MLAA
FSAA
MSAA
etc...
