360 VS PS3: CoD Games?

Several times i've noticed that when playing 360 i get a decent amount of kills and not always on the top of the leader board but yesterday i was at my cousins and played a few rounds of black ops on tdm online, I always got more than 20 kills and top of the leader board, It surprised me because i hadn't played a CoD game for about 6 months and i'd never played black ops up until yesterday. So anybody else noticed that 360 players are a lot better when playing against ps3 players on there own consoles and on 360 consoles?