I can't see why Disney has slowly strategically put these things on certain ABC properties (and Glee that one time) when they should be advertising during EVERYTHING. I saw the same Puss in Boots commercial twice in a commercial break. Granted, it's coming out today, but I also see Happy Feet 2, Twilight and jack and Jill multiple times during commercial breaks lately. They need to amp it up.
And by no means should they NOT advertise this on How I met Your Mother. One of the stars of the show is in the film... that's how they usually market these things. I remember seeing an ad for A Bug's Life once during Spin City, and Richard Kind was talking about his character.