Totally different. Apple totally relies on 3rd party and has no real mascot. When people think of Nintendo they think of Mario, Sega with Sonic, Microsoft with Halo, and Sony with a few titles. When people think of Apple no major thing comes to mind.
Nintendo is pretty much rock solid, they have AAA first party titles which people buy the system for. Sony and MS have CoD which makes people buy their systems. When people buy an iTouch or iPhone it's for other things and gaming is more of a capability that is not the main function.
Also, the platform itself has major problems. Touch only controls are fun but are terrible for FPS and many other genres. Apple also produces no games on their own so their whole library depends on the willingness of other companies to invest in it.
Apple has a long way to go to overthrow any of the gaming companies.
