Meh. I'd say ArmA II has it beat both in terms of realism, and fun factor. In ArmA II they just let you loose and allow you to pursue several different missions across a vast and detailed map. There are tons of different weapons available, any vehicle is usable, the action is very dynamic.
I also had high hopes for Operation Flashpoint: Dragon Rising, but I was inevitably let down by how canned it feels, the gun sound effects sound like someone firing off a capgun in a confined space, and nothing ever feels dynamic. The action, while fun at times, is fairly blah and can feel pretty scripted. I guess it all depends on what you like.
My $0.02
