It is unknown if forge will be in it but firefight will with an awesome new feature-marine allies!Yes, it was secretly announced at E3 in a press conferenceYes. The Firefight map is called Installation 04 and is set around one of Halo's Beam Emitters. Theater will also be included, but only for Multiplayer.It will have a new Firefight map, Installation 4, and will likely include forge as multiplayer runs on the Reach engine.
person asking this question, have you actually taken the time to read through anyh halo anniversary info? if so youd know the answer before you asked a pointless question