A Few Questions. On Xbox 360 Live in Halo 3....?

[halo3pwnag3]

Can you make your own matchmaking games ( or if you make a custom game will people quikly join like in matchmaking?) or do you have to go to matchmaking to randomize a game?
And how do you earn 'rep'?
how come nobody EVER has their headsets to speak?!

 

[realivelite]

Matchmaking games are always completely random, only people on your friends or recent players list can join your custom game, and you get rep from people submitting a positive player review about you. As for the headset thing, I don't know but it's been annoying me.