You people need to open your minds a bit more and stop acting like if Nintendo doesn't do something there must be a very good reason for it, even when there really isn't.
If I go and buy a PC game, it's expected I will be able to play it online, unless it's one of those rare extremely single-player centric games. I mean, what if you bought Timesplitters 3 and it didn't have multiplayer? Well on PS2 and Xbox everyone is going to expect that it has online as well. And at least 25 to 50% of people are going to choose the PS2 or Xbox version because of that. No one expects a GCN game to be online because quite frankly, Nintendo was just wimpy and scared it won't work out this generation, and just ended up making a big blunder instead. But what would be a Nintendo console theses days without it's very own blunder right? Look at Halo 2. OMG OMG it's another Halo!!!! And you go online!!! Apparently this thought crossed the minds of at least 2.4 million people who bought it the day it came out. Halo 2 earned more money on it's first day (over 130 million dollars) than any movie in history has made its opening day. Look at how much people play for MMORPG's on PC. Look at how much people play Warcraft III and Counter-Strike online (both of which are FREE. Nintendo says it can't do free online this generation because of costs...um, i've been playing free online for years on PC, Nintendo doesn't need to set up a centralized online system like Microsoft, it can let third parties handle their own servers like PS2 and PC).
Nintendo releases a broadband adaptor you literally have to hunt down in an epic month long quest, and then decide not to support it at all.
Anway, Nintendo made a big mistake. That's a fact. If everyone and their brother is peeing their pants at the though of Halo 2 or Gran Turismo 4 online then what's to stop them from peeing their pants at Mario Kart online or some other nintendo franchise. Remember Mario Kart 64 sold more copies in the US alone than Halo sold worldwide. And I'm not even going to mention Goldeneye. Many of you have no idea how much of the Goldeneye fanbase Nintendo lost to Xbox/Halo just because the GCN launched in a weird kid's color without a Nintendo published FPS (IMO they should have delayed Perfect Dark a year a half and released it at GCN launch, same for Conker's bad fur day...If those two along with Eternal Darkness were at GCN launch Xbox would be a distant third right now).