MW2 meets my expectations, but because I didn't have that high expectations compared to PS3 exclusives.
It is of course strange games like Halo and Call of Duty (or certain sports games) don't receive a similar penalty for being so similar to past titles, while for other games like for example Ratchet & Clank: TOD (which had quite a bit of unique gameplay, like the great sixaxis controlled flight sections) do.
So there's clear bias involved, especially from the US press it seems.