If you don't have a original 3DS, then yes it's worth it. Also, remember for North America residents, if you buy a 3DSXL and a copy of either Luigis Mansion 2 or the new 3DS Pokemon Mystery Dungeon game and register both the console and game on the NOA club nintendo website now, you can claim a free download copy of one of the following games
Super Mario 3D Land
Star Fox 64 3D
Art Academy 3DS
Freakyforms Deluxe
Professor Layton and the Miracle Mask
The event ends April 30.
(Hint: Get Mario 3D land, layton or Starfox, don't blow it on art academy like I did in the europe equivalent).
Now that that is out of the way, I would say absolutely. The 3DS has a pretty good selection of games to choose from right now, and it looks like it's only getting better from here.
I'm just going to start throwing things out because I have no idea what genres you like, feel free to say so and I'll make some better recommendations
In general though I would highly recommend :
Kid Icarus Uprising (The writing in this game is brilliant and always hilarious, it's by the same guy who makes the Smash Bros games, and it really shows. Very Polished, but the control scheme takes some getting used to. My Most played retail 3DS game). The online mode is great too, though I'm not sur eif anyone else on SP even has this game other than me.
Super Mario 3D Land (You could claim it for free with the above offer!)
Virtues Last Reward (Also on PSvita, it's a visual novel, but you should play the DS game 999: Nine Hours, Nine Persons, Nine Doors first, because this one is a sequel to it)
Theathrhythm: Final Fantasy
New Super Mario Bros 2
Tales of the Abyss. If you like RPGs and haven't played the PS2 version, it's probably worth playing.
Resident Evil Revelations: The best horror/shooter (only?) on the console. It's probably the best looking game too. The Consoles and PC are all getting a higher res port with some improvements in May though, so those versions might be preferable.
Games I would also say are worth a play, but might not be for everyone:
Sonic Generations: Decent 2D platformer. Good online.
Ghost Recon Shadow wars. A good tactical grid based game, kinda like fire emblem. Possibly redundant now that Fire Emblem : awakening is out.
Paper Mario Sticker Star: A good game. Just doesn't reach the lofty heights set by the previous Gamecube and N64 games. Lost a lot of the rpg elements too

Rayman Origins: If you can't get on eof the console or PC versions.
Mario Kart 7: It's ok. Probably the weakest Mario Kart for a long time though.