Well before the NES, there was no real predefined controller, the goal of a controller is to make sure you can fluidly make decisions and have it acted out as easily as possible on screen. The NES defined it by having basic buttons, and the revolutionary : D-pad.
Then came the SNES which is the one to use shoulder buttons, and that worked out well along with the button scheme in which Sony obviously copied and improved a little on bit by bit.
The controller today has to fit a wide variety of games without you having to buy a seperate assessory to play the game. It doesnt have to be perfect, but it has to be versitle enough and Nintendo did make one that fits just about every game. The controller defines what the game is able to be made on a console IMO, try playing a fighting game that is not Smash bros on the GC controller like Capcom vs SNK 2...its maddening..the Xbox is similiar, but not as bad, but definetly not as good as the PS2's layout as i had trouble with it too(doesnt beat joystick for many dont get me wrong). Now try playing FPS on a SNES or NES controller..its much harder to do than say Xbox's controller or with a Mouse.
Therefore i feel Revolution's controller IS revolutionary....no controller really had the limelight of being the default controller that looks like this(most if there are any, are probably gimmicks like the Super Scope of the Power Glove). However does it mean its effective? Thats unknown at this point...however it DOES have potential...Nintendo just has to show it, and try to prove that a wide variety of games can be played on it the same way as the other controllers.
Well it gone off track a bit but i think i got my point accross...controllers matter a whole ton, thats why Sony doesnt change theirs alot beside's its shape from their PS ones that they copied from Nintendo, it freaking works for almost all games. I hate hard to press buttons, i hate wierd controller sticks smoothness in motions, and i hate those that break easily >_>; Like most third parties.