Been messing around with Bad Company 2, which is fairly fun (for a battlefield game) but definitely not the CoD4 killer I've been hearing about.
[rant]
Giving players something to work towards with the unlock system is cool and all, but they fucked up big time with how pathetically weak the starting weapons are compared to the shit you unlock after ~50+ hours of playtime.
The netcode is completely fucked. If I play ANY other mutiplayer game on a decent nearby server, I'm under 30 ping. Always.
In BC2, you might see a single person after hopping from three servers with a sub 100 ping, and it'll be between 85-95. Combine this with the fact that weapons aren't hitscan, and all projectiles have travel time/drop; good luck hitting shit if you're used to playing shooters with a low ping.
Then there's the team stacking problem.
In the majority of servers, teams are stacked HARD. This results in the losing team hemorrhaging players, then players from the stacked team getting autobalanced to the losing team.. and then leaving because being on the receiving end of the rape fest sucks. This sort of thing happens a LOT, and could have been easily fixed by adding a team scramble option.
There's also the complete lack of teamwork, which means two good players in a tank or helicopter can and will dominate 16 terrible players, since taking them down will require a coordinated effort or extreme dumb luck.
[/rant]
Anyway, despite all of the bullshit; if you can land yourself on a team that's actually working together, the game is pretty awesome.