So far I'm really liking the game. The artwork is great but the 3D models still have the infamous Nintendo DS "jaggies" if that matters to you (I don't mind it). I haven't played too much of it yet though (just about an hour's worth), so I can't give you a solid answer as to whether it's worth getting the 3DS. I'm also buying The Legend of Zelda Ocarina of Time from a friend, so those two games alone will make it worth it, for me, to get the 3DS. The 3D effect does take some time to get used to and you really do have to have the 3DS directly in front of you for the full-depth 3D.
If you're a big Fire Emblem fan, I think this is a great game in the series. It's got Path of Radiance/Radiant Dawn's 3D-ish battle map and battle animations, Sacred Stone's world map, and classic Fire Emblem strategy gameplay. The dialogue seems to be more engaging so connecting to characters will be easier if that's your thing (kind of reminds me of Tales of Symphonia).