Halo does appear to be to be the best multiplayer option FPS for ALL THE CONSOLES. In fact, it's muliplayerability goes above and beyond perhaps even all the console FPS put together.
It is quite refeshing afterplaying game after game of 4 player shooter action to slap in Halo and go for the 16 player ride of your life.
But multiplayer aside, Halo does have it's flaws. It's nice to have a co-op in the story mode, but then again compared to other shooters it seems at a snails pace. It may make you SLEEPY, especially aftet comparing it to multiplayer.
Other than the speed issue (which seems to enhance multiplayer because opponents are easier to shoot) Halo seems to be a near perfect. The graphics look stellar, the music is fine tuned, even the voiceover is well done.
I would recommend this game to anyone with an Xbox -- those that love FPShooters, buy two.