Madness. Keyboard and mouse was an adjustment. Netcode was terrible. About it, but that's me. Either way, Fyre's plea that there's an outlet for playing Halo:CE online is unfounded. This is the closest thing we'll get. Get optimistic!
It's not just K/B + M, the gunplay doesn't have the same feel, which could be tied to the game being designed inherently for the Xbox controller, but it's not right. The movement and gunplay just doesn't flow as well as it does on Xbox. I would be optimistic if Halo CEA was Halo CE MP on XBL on 360, but having to buy a new console, for a version of the game I'm not terribly interested in playing, no thanks.