Start with Halo end with BLOPS?

I feel like that is a little messed up that Halo went first and BLOSP 2 was the show finale / closer what are they thinking? Save the best for last?

Microsoft wanted start with a bang and put their best foot forward. Believe me, Microsoft is far more interested in the success of Halo 4 than Blops 2. They likely ended with Blops 2 because its not theirs. its not an exclusive so they stick it at the end.