I'd say killzone 2 has a way better community than resistance 2. Haven't really played much the last 3 weeks since i got banned for a week for using bad language on my mic with a sony rep in the room. Usually i can find games 24-7 but often times people play the small maps with twice as many people as the maps were made for. I wanted to play yesterday and the day before but every room i saw had that happening so i just played another game. 3 weeks off really ruined my aim because i was pretty much dominating everygame a month ago unless a whole team would be boosting and hiding behind robots. Yeah about a month ago i was even getting big games on the new maps, but most douches use shotguns and hide behind robots.
It's one of the best ps3 games i have played online when people aren't putting robots behind every corner, grenade spamming, or boosting. Picking the right room can be hard on certain days.