Gamecube has those funny mini-CDs too. Reason why Playstation dominated N64 was the the PS could play "backups". I have, errr I mean I know someone, who has a N64 with about 20 cartridges, but also has a DC with about 70 "backup" games. Too bad about the end of the DC line, very underrated, great graphics and games. DC will be around for quite a while, Sega did sell almost 6M units with most of them in the US. If "my friend" would've looked harder he no doubt could have over 150 or so backup DC games.
I predict the Gamecube will be the last console for Nintendo too, as MS and Sony will dominate. PS2 is vastly overhyped, overrated and overpriced. Glad I sold mine on Egay.