Normally I would tell people to search for the answer but I'm in a good mood.
Ok, many people have the misconception that the friend code thing is a barrier. Now when I say that, I know people think that you have to find someone online first, get their code so you can even play someone online. Well the fact is that it's false.
I'll use my DS as an example.
All I have to do for Mario Kart DS is hit the WiFi option, my DS connects to the Nintendo WiFi servers. Now I can choose from four options. Friends (all the people you registered are here), Rivals, Regional, and Worldwide.
Selecting Friends means that the server looks for ONLY your friends to see if they are online, and put you in a match against them. Thats the only thing Friend code is for, FOR SPECIFIC people you want to play. Now if I choose regional, I just wait for some people to join (it doesn't take long at all) and then the game starts. No adding people and whatnot.
True there could be possibly some additional things that Nintendo could add, but with millions of gamers in the world a number system is much better otherwise we'd see a bunch of crap for usernames.
The nintendo wii will have a lobby for online multiplayer. Seeing how the DS was the first for Nintendo, they obvisually have a much better idea on how online can be done using the current system they already have in place.
