They are "covenant" but are a separate rebel faction. If you play spartan ops you see some of there leaders, and what gap between halo 3 and 4. You have to remember that there is a four year gap between the two.
Yes, and like Mayh3m said, they need to carry it out in a helpful manner. Not just something people can play just to play.
I think 343 could execute the game much better at launch with a beta.