Welcome aboard man.
Things of interest include, but are not limited to:
The Events page, where all your boosting needs can be met, or started.
The Competitions page, where the weekly, and more, competitions go down.
Both Trade Threads, one for 360 games only, one for Random Shat. Better than Game Stop.
Meta's Waffle List, awesome list of easy gamer score games, we call em waffles here.
Have a blast at the site. Feel free to check out the "What's Behind YOUR GamerTag" thread as well.