i really like this game as far as MP is concerend. i haven't tried SP. i can't compare this game to Halo 2,3, and ODST because i never played those enough to judge them, esp. MP.
the only issue i have with the game is the voting system. numerous times it's happened to me where infection or safe haven (basically the same mode) gets voted 3 or 4 times in a row. i don't think they should have as an option a mode that you played prior. and then you can't back out once it's voted. that's bull . i paid 60$ for the game, i should be able to back out whenever the i want.
oh, and another problem i have is that some of the MP levels kind of suck. don't get me wrong, there are great ones, but some of them are stinkers. some of them just seem redundant, esp. the ones that are created with the forge architecture. hopefully the DLC makes up for that.
other than that, i really like the game.