N64 was a great console. Super Mario 64... Ocarina of Time... Superman 64 :D kidding!
With N64 we first experienced home console gaming with a joystick and a true 3D world with Mario 64! Not to mention rumble features!
The console itself was awesome as so was the controller... unfortunately Nintendo made a serious of big mistakes in the developer world and played for it.
I think Sony`s great advantage was expanding what Sega did with Genesis/Mega Drive: go for the cool console and go for the cool kids. Of course this meant non-kiddie like games like N64 and GC were branded with, therefore attracting an older audience.
With Sony doing everything right, Playstation became another word for videogames, like Nintendo before it.
After N64 a lot of damage was done and there wasn`t a single thing that Nintendo could do to stop PS2. No matter if Nintendo even played to developers to bring their games to GC, PS2 would still have been the great winner.
Of course it surely didn`t help releasing the console a year after PS2. That was just baaad!
Personally i had a lot of fun with GC. Not only with Nintendo games but with 3rd party games (RE4, Bloody Roar, ISS, Red Faction II, Monkey ball, Soni Ad., etc).
Great console but with a fate already set in stone!