I'm looking forward this as my first FPS that I purchased was actually BF 1942 way back. The trailers look amazing and I think it's fairly obvious at this point that BF is going to have a technical edge on whatever CoD comes out in November...
I do actually enjoy CoD too though - I don't think the two are mutually exclusive because they're so different by nature. I've logged more hours on MW2 than any other online FPS (didn't play COD4 though or any of the recent BFs extensively online), but that might also be because I have lots of friends to play it with so that definitely adds to the appeal factor. Sometimes I find myself wishing that they would make a Battlefield game without all the tanks and jets and stuff, and just more pure infantry play, but with that great BF quality and feel - not that jets and stuff aren't awesome, I would just prefer more straightup gunplay sometimes. Still most likely getting BF3 on release though, but gotta build that new rig first to handle it