I personaly have one since like.... a week after the zelda ocarina of time 3D release and I love it so far ! I think it's a great handle console that have a lot of potential(and the 3ds is mindblowing the first time you play it xD....). Although I can't wait for the time around christmas since there will be a lot of new releases for it there.
So yeah I'll say the most addicting function of it is probably to play with the plaza and get to meet people with it. Like I go to conventions and brought it into them and wow, so fun to meet this many people going around with 3ds. I think I was becoming a bit too addict to the street pass pfff. The AR game a pretty impressive too, can't wait to see a game that might use it haha !
Anyway I'll leave the conversation open ! Talk about it !