As the 1 year anniversery of Halo 3 today, Bungie announced what they didn't announce at E3. The expansion to Halo 3. The trailer came out today, it doesnt reveal anything, it just shows what is to believed to be Metropolis, a city on earth that was attacked and destroyed in Halo 2, being attacked by in my opinion, space pods with Convenent in them. It is probably just that part of the game through someone elses eyes or something like that. Check out the trailer
http://www.bungie.net/
EDIT: When I re-watched the trailer in HD, I spotted a few Traxus buildings, which was the company that found The Ark in Halo 3. But, post what you see here.