I'll agree with this. Most of the people I know have 360's and their friends got them to play together.
Ironically, I got a PS3 anyway and I'm definitely the biggest online gamer out of all my friends :P
Platinums: Red Dead Redemption, Killzone 2, LittleBigPlanet, Terminator Salvation, Uncharted 1, inFamous Second Son, Rocket League