Campaign is the exact same game as Halo CE including physics. You can switch to classic mode in game to switch to old school graphics to compare the difference (wont be noticable).
Quote
Don’t like the new assets or wish to experience the originals? The game also ships with the classic graphics with a way to switch between them at a press of a button (confirmed by 343i’s David Ellis)
However the online will be on Reach's engine and will play with Reach players with the new "Classic playlist" which inlcudes the classic halo 1 maps but on reach engine w/ reach. Reason for doing this is they said they didn't want the games multiplayer to cut the Reach playerbase in half.
Quote
With this update we also get 7 new Classic multiplayer maps. Those wanting the original multiplayer experience will be saddened as the maps look to be for Halo: Reach. The graphics, player models, and animations all confirm this. The maps shown in the trailer were Hang ‘em High, Damnation, and Battle Creek. It is assumed that Anniversary will ship similar to ODST, which had 2 discs. We’ll most likely see 1 disc for the remake and 1 disc with the full Reach multiplayer experience and the new maps. If so, I am glad to see actual remakes instead of blocky-gray Forge maps. While all parties may not agree on this, it really is the best approach so as not to split the player base, and give Reach new life a year after its release date. This will also make for a clean break when Halo 4 (also announced!) comes out in late 2012.
Finally, game wont be full retail price.
This post was edited by D2-Infection on Jun 6 2011 10:08pm