If I were you I would wait until either one gets several games that really appeal to you. Possibly by then, you might reap the advantage of price cuts/redesigns as well.
However, I would say that at it's current price one can't really go wrong with the 3DS. It already has a 3D Mario Platformer, a remake of the highest rated game of all time, Tales of the Abyss port, Starfox 64 remake, Pilotwings, Street Fighter, Nintendogs and Cats, Blazblue, etc. In the near future, it's going to get Mario Kart, Monster Hunter 3G (and 4 in a few years), Mario Tennis, Resident Evil: R, Kid Icarus, Bravely Default. And don't even get me started on the epic DS library that can be played via full BC (minus Guitar Hero due the the pheripheral not fitting).
