Arbiter and Master Chief make a good team.
I started playing Halo3 on November, 2007. It was very addictive. The campaign was fun, the Arbiter and Master Chief 117 are pure ownage. So was Sgt. Johnson. Sad that he died though.
My favourite thing in Halo2 are the grenades. They are awesome against enemies. Especially the Plasma Grenades that stick to you. They blow up the Brutes into pieces. I love it when The Arbiter uses the Energy sword, he goes crazy. The only annoying thing in Halo3 is that you can't run. But still, Halo owns!
I hope Halo: ODST will be very successful, I think Halo Wars is gonna suck, since it's a real-time strategy game. But let's hope for the best.
The Halo3 guns and weapons are amazing. Very unique shapes of guns, and creative names. Like Carbine, Gravity Hammer etc.
I heard there was going to be a movie about Halo, i hope Samuel Jackson will be Sgt. Johnson. I also hope the movie HALO will be very successful.
Peace!