Game of the year: Bioshock or Halo3?

So I heard an interview today and one of the subjects was "Game of the year." The two contenders are BioShock and Halo3. My question to you is this; is there really even a comparison? Halo3 came out today, so of course its going to be more popular today, but let's look at is from the player perspective.

Halo3: Third installment of the halo series, from my point of view its somewhat of a prettier halo 1+ 2. It might be the best halo ever, but not the best game ever

BioShock: Brand new idea, looked great, amazing game play, fantastic story line.

Everyone has their favorite for one reason or another, but I still have to call BioShock game of the year.

P.S. It really doesn't make sense to name something "blank of the year" until the year is actually over and you have had time to check out all the options. A more appropriate title would be blank of the year - so far". There is my one and half cents for the day.