Try shooting a tree into pieces. Oh... can't do that? Cryengine 2 can. http://www.youtube.com/watch?v=O4sphyDhO5E
Try amassing 8000 barrels and letting physics take care of it... oh ya... Arma 2 can't. http://www.youtube.com/watch?v=e0R9veCqr2U
Hell, the Arma 2 engine can't even do 64-bit. Oh... on top of that, it can't even load textures properly when maxed on a 32-bit machine.
To even compare Arma 2's engine to the Crytek Engine or to put it in the same league is just ridiculous. Mind you I'm not a fan of Crysis as they limited the "open-ended" game to a particular path when they didn't need to. But engine wise... that Cryengine is so far ahead of everything else it's not even funny.
The ONLY thing that Arma 2 engine has going for it is its AI system which is very commendable but due to it's complexity is highly bugged. Otherwise the engine is old and flawed and BIS continues to propagate it.
Let's leave the fanboy comments from the posts ok?