See, what people don't realize is that revolutionary games have been coming out. It's more like evolution than just a BAM hit you in the face kind of thing. Look at games like Battlefield 1942 and UT2004 really changing the gameplay of a first person shooter into something different by the way they use the vehicles (orginally tribes). Then you have games like Savage that are fusing gametypes like RTS and FPS.
Unfortunately because it's a slow change many of these games don't get as much attention as they should. Also many of these games fall to just using the "revolutionary item" as a gimmick and not fully expanding the potential that it could have.