Sorry to say fan boy but I own both and the 3DS has better games in some aspects as well as quality. I still have faith in Sony with the Vita but for now ill keep on playing my ps1 classics. And fire emblem on my 3DS.
Add me on Xbox: iSnowPro/PSN: iSnowPro/3DS: 3780-9232-8066
It may have been pretty close, but 3DS wins for now since Fire Emblem was just released. And with Monster Hunter, Animal Crossing, Luigi's Mansion, Castlevania, and Pokemon around the corner I'd say the Vita has an uphill battle.
I'll give the edge to 3DS since Kid Icarus and Super Mario 3D Land were some of the most fun handheld experiences I've had in a long time. If it weren't for those two games, then I'd probably vote for Vita. I haven't played Fire Emblem yet, but I'm hearing that it's pretty awesome as well. There are some very good games on Vita, but nothing I'd consider a "must have".
The poll is a little unfair since 3DS has had almost twice as much time on the market.