diablo2.. theres less cheating in closed server, however u still have the gay botters.
i was talking to a friend of mine about DS and nintendo and wheres it heading. i duno said that like.. since friendcodes are in... its very hard to start an MMORPG, becase nintendo has always been child friendly.
thats why u can never play mario kart to its full extent against randoms, unless by a online community.
also they spent a heap on creating friendcodes and i doubt they will destroy the whole thing, for an MMORPG. + there is lag in 4 player mario kart.. imagine when u have thousands of people trying to log on, using a DS which has only about 180 MHz of power.