Despite the fanboys and the hype, Halo is still a good series, and at least their sequels (ODST excluded, but they even admitted it was more of an expansion pack, as shown by the lowered price) are given an overhaul each time, instead of having the same game 3, and soon to be 4 times in a row from the CoD franchise. Halo has a decent campaign, though it is very much style over substance (or at least story; it is long enough imo), and solid multiplayer mechanics that give great, albeit a little arcade-ish, gameplay.
Back to Black Ops:
It won't sell as well as MW2, and imo, CoD is simply running on hype now as most people are seem sick of CoD games, but will still buy the next one because "everyone else will". They should do what ubisoft plan to do with the AC series and wait a couple of years before releasing the next game, allowing the hype to build up again.
If there is another CoD game next year, it will sell drastically less than Black Ops unless Black Ops is a big success (as in, real big).
