1 - Games are organized on the IRC channel, you can also check the schedule in the sticky.
2 - The E, QD, andicirk (captain-custard), Shade (he hasn't been on in a while)...
3 - Mostly coop, although the occasional PvP is fun.
4 - The latest nightly build and the new MediaVPs, or else no MediaVPs. Make sure to get the Multi Mission Pack.