French Halo fansite, Halo-Destiny has somehow gotten their hands on the upcoming map pack for Halo: Reach. And apparently one of the three maps being released is designed specifically for Firefight.
That map is Unearthed an open Firefight map designed specifically for four players.
As for the other two maps, Condemned appears to be designed specifically for four versus four team slayer skirmishes, while Highlands focuses on big team battle gametypes, created for 8-16 players.
It seems like Bungie are taking a scattershot approach to this new map pack, designing three different maps for three distinct types of players. Considering that you have to pay for all three as part of a package, that may upset some players, but Halo fans that enjoy all facets of the game - ie me - will most likely be happy to pay for a map pack that will presumably sell for 800 Microsoft points.
Some blurry pics, taken from Halo-Destiny, can be seen below.
Thanks to Dax01 at Neogaf for spotting this.