http://www.ign.com/videos/2011/08/26/halo-ce-anniversary-mulitplayer-vidoc
At about 52 seconds into that video, you can make out a blury “Headlong” right below “Beaver Creek” on a whiteboard titled “Classics” while talking about the maps they chose. They blurred it out a bit, and it went by fast, but it seems almost certain to me now that the Halo 2 map is Headlong.
I’m sure this will make all of you Headlong supporters thrilled lol. Personally I would have preferred Waterworks or Zanzibar, but oh well.
Note that since it hasn’t been officially revealed, this could just be speculation. However, it seems pretty evident to me that the final map to be revealed will be a Headlong remake.
PS: Sorry for the cheesy and cliche title, but it’s short and gets the point across 
Headlong is sick, I miss super bouncing onto X-Building. But why does every map they choose have to be large? What happened to classic maps like Lockout and Midship?
Yes!
Headlong and ascension were my favorite maps in the series!
Now both are remade!
> Headlong is sick, I miss super bouncing onto X-Building. But why does every map they choose have to be large? What happened to classic maps like Lockout and Midship?
There’s only 2 large maps so far.
And Damnation, Prisoner, and BC kick the -Yoink- out of Midship.
Headlong please please please please be true. 
On a side note, it’s funny how convienient Damnation and Prisoner are for Halo: Reach AA gameplay. But that’s not meant as a criticism. I just find the novelty of how these 10 year old maps just work so perfectly for the Jetpack. xD