I own 10 3DS games (and 10 Vita games):
Mario 3DS - awesome awesome
Zelda OoT - why did I buy this, I played this game before.
Re: Rev - haven't played it much, seems kind of iffy
Pushmo - ok game, worth the $5/6 for sure.
Musou - Switching characters is cool, but not being able to just pick a character and play is super lame; having to play as your own generic guy is lame; 15-20fps PS2 graphics
Pilotwings - fun for an hour
SSFIV - sucks ass, 3DS is not good for fighting game controls. Why did I buy this? Oh yeah, launch drought

Layton 5 - Hot hot hot stuff, need to finish #4 so I can play this
Gundam the 3d battle - ok C+ UC gundam action game; nostalgia
Beyond the Labyrinth - ok Etrian Odyssey extreme low budget dungeon crawler by Tri-ace. I like it, but it's slow and many many floors of the same thing.
Will be buying Kid Icarus and Kingdom Hearts 3DS in the next month. After that, there's nothing I'm interested in on the 3DS until the TBD stuff starts getting dates like Paper Mario, Fire Emblem, and still nothing much in the horizon besides those.
Right now I'd say the only games worth buying on the system are Mario, Mario Kart (if you like MK, I don't), Zelda (if you never played OoT, I have) and maybe RE. Pushmo too since it's cheap. But yeah, a year+ in and there's still barely enough titles to justify the system. After playing the 3DS for a year, I've finished exactly 1 game on it (Mario) and technically I haven't even finished that one because I'm still going through the Special Worlds post-game. Just not much compelling software there. I'm sure it'll get better stuff next year. Will try out the Bravely Default demo this week but I have a feeling that game is going to suck hard.