Going completely against the grain here...
I think people dramatically over state Nintendo. Sure, they have made plenty of innovations but these ideas certainly wouldn't 'vanish' or never be seen if Nintendo wasn't around. It has absolutely nothing to do with the company of Nintendo merely the people working for Nintendo generating ideas. You don't think these people would land elsewhere?
People act as if Nintendo is just light years ahead of the competition? Hardly.
Nintendo has lived off of a core group of fans and generally regarded as a very positive child oriented system. (IE: I personally have bought Nintendo systems just because they were a Nintendo system with Mario, Zelda, etc games...Gamecube sticks out). I think most software on Nintendo systems dating back to the N64 (Outside of Nintendo software) has been pretty mediocre as a whole.
I think you may lose some of the charm and nostalgia of not having a Nintendo...but truly the games would drastically improve IMHO.
I think that the argument that Nintendo 'invented' ______ or 'introduced' ______ is just a cop out argument. It's acting as if Nintendo had Einstein moments that no one would have discovered at any point down the road. Which is abundantly false IMO.