From what I've heard, it will run you about $30–$40(?), so a pretty good deal. It will include 7(?) new multiplayer maps, which are compatible with Reach, and a fairly unknown firefight map. The gameplay of the campaign will remain identical to Halo CE, but with bright-and-shiny new graphics+audio, achievements, LIVE co-op, and terminals. If you were to pre-order, you would receive an in-game skull causing dead grunts to explode, and Master Chief armor for your Xbox avatar. For all the stuff you get, and for the added nostalgia and fond memories of the first Halo game, all for a cheaper than normal price I'd say it's worth the buy.