As much as the gamer in me would love to stand up and shout "WUT NINTENDOE!? TEH WII IS 4 N00BS" I basically have to agree with you. While Nintendo seems completely unable to innovate in terms of story and character (see Zero Punctuation's review of Super Mario Galaxy for a great explanation), they are really the only major company keeping innovation in gameplay going. With the Rumble Pack on the N64, the Wiimote and now the Wiifit, Nintendo seems to understand the exact same playing experience gets stale after awhile.
That said, I really enjoyed the first Gears of War. I'm looking forward to the second one, but I'm not looking for anything genre shattering.
While writing this I came up with an analogy that at least makes sense to me. When a high point in the FPS genre comes out (let's call it Bioshock), you can compare it to a Monet in Impressionism. As an artist you have two options: either you try to perfect the Impressionist design even more (Gears of War 2) or you go off and become Cubist (Super Mario Galaxy).
Sorry it's early and I'm heading off to class. This is what happens when you make a college student think.