I am most definately looking forward to OFP2. I like OFP1, although animations were poor, voices were poor and missions seemed to bug out too easily. It was the sheer size, scope and "mod-a-bility" that made it great.
I then bought ARMA, which i thought was just a slightly prettier and tweaked version of OFP. But again, although slightly improved animations, everything still felt wooden. Animation transitions detracted from the realism the game is supposed to portray.
From looking at videos and watching the Dev interviews on OFP2 there seems to be much more advancement of its genre than the new ARMA2. Codemasters seem to be really keen on keeping the realism from the first OFP, but expanding the areas which let the original, and its spiritual successors down. i.e. animations, player/human/environment physics, AI, Voice acting.
The new ARMA2 seems to be yet another re-hash of ARMA, but I'll reserve my judgment until I've played them for myself