Battlefield BC 2: I can really appreciate the more realistic bullet and weapon physics, compared to MW2. It seems that the calculation elements that go into taking-and-making shots does more justice to reality. Sniping, specifically, redefines long-range engagements for a lot of the migrating MW2 players, and you'll notice far less self-proclaimed "snipers" roaming around the frontlines, no-scoping -- or sniping, period. Hooray for that!
I do wish they kept the claymore mines, though... And it would help if we could prone (for console users).
When it comes to MW2 (which I'm also immersed in these days), it's no secret that you're basically forced to learn how to deal with CQB, since most, if not all, maps are close-to-medium range. You either adapt or get slaughtered. But I don't think of it as necessarily a bad thing, considering a lot of my MW2 "skills" are applicable to other games, such as BFBC2.
Hah, I have been wondering if getting Urban Combat advice from here would help my gameplay at all. :-D