Nintendo is actually one of the only 1stParty publishers that takes the time to invest in a Research&Development department.
When they have an idea (that's beyond visuals), it usually becomes industry standard:
Analogue Stick, D-pad, Save Battery, Bios Save, 4 controler ports, sholder buttons, portable games (started with their Game&Watch), light guns, etc......... to name a few.
They've had failures as well, and that's proof that they try to innovate.
Competition in games is now at a new level, and their's not a clear defeat anymore... (I'm lookin' at you 3DO, Jaguar, Game.com, TG16)
so don't expect portable wars to be any different... if you want all the goods now-days you have to buy all the consoles..... if not, all you can do is sit back and hate on systems you truely want and don't have.
I'm in support of the DS, because it actually points a finger at developers and says: "I bet you can't think of something creative! Go ahead try!"