Maybe to you, but to others it blew them away. That's why it has a Metacritic score of 96, and has won god knows how many game awards.
Even though I love CoD4, I don't see where the innovation is, pretty much just a mod for CoD2. The MP is excellent though, and that is why it is a highly rated game. But if you look at the latest Valve release, the next episode in the Half Life series, with an excellent story. TF2 arguable the best MP game released last year and Portal easily the best game of last year. Then you look at Oblivion and I think most people would argree they took a step back with Oblivion, to make it friendly for console players (nothing wrong with that, but it's not reallly inovation).
Compare this to the innovation with Steam. The games coming out this year, Left 4 Dead, The Crossing, adding match making features on all their MP games. And the excellent mod support they offer.
This is when you start to see how good Valve are.
Half Life is far from over.