Why do I think this? Simple, every generation of game consoles either gave us or popularized something which is now standard in the industry.
The first generation gave us video game consoles themselves and controllers, obviously, that's standard.
The second generation gave us actual different games in consoles that were played via cartridge, as opposed to just one or two games built in (and in the case of the Magnavox from Gen I, using "cartridges" that were really jumpers). While (sans the DS and 3DS) the industry doesn't use cartridges anymore, having switched to disk-based mediums, could you imagine a world where you can only play games that are hard-wired into a console? And nothing else?
The third generation gave us the D-Pad, which every console has some variant of. No further explanation needed.
The fourth generation gave us the shoulder triggers, L and R. Every controller has one, with the PS3 having 4 and the Wii's being on the Classic Controller and Classic Controller Pro.
The fifth generation gave us the Control Stick on the Nintendo 64, which led to the Analogue Stick on the PlayStation. Quite obviously, every consoles (sans the DS) has some form of an analogue stick or nub. (With the 3DS having an analogue nub-slide-pad-thingy-ma-bob-kajigger)
The sixth generation gave us online game play. Microsoft has Xbox LIVE, Sony has PlayStation Network, and Nintendo has Nintendo Wi-Fi Connection.
Now, what about the current generation? What did this game bring that really changed the tables of game play? HD graphics? Not really, graphics don't change game play, just make it look better. Wireless controllers? Nope, Nintendo had the Wavebird for the GameCube and they had third party wireless controllers for the PS2 and Xbox. Hey, look at that, the Wii allows motion controls. I mean, yes the PS3 had some motion control before the Move, but it wasn't like the Wii. I mean, you move the remote left, your character looks/turns left. You move the remote up, they look/turn up. Then the Motion+ allowing 1:1 accuracy. Some people say the Wii Remote+ just rips-off the Move's 1:1 accuracy, but it's just putting the Motion+ into the regular Wii Remote. Based on the sales of the Wii, as well as Sony and Microsoft releasing their own form of motion control. I think motion controlled game play is the influential thing from this generation of video gaming.
