why, since the halo 3 update, i have not been getting exp?

[Jack B]

i win the games and get no overall exp or any exp for the specific game type..
it really annoying because i'm not progressing on the game!! and i've been kicking ass all day lol.
Any help would be appreciated.

gamertag: jackboybruce - if you want to get some of the new achievements with me.. seeing how no-one on my friends list plays it anymore.