Yeah, I don't think 3DS is "lead" this time around, the second screen is telling. Even Virtue's Last Reward's interface was extensively designed around both screens, despite the top screen becoming the gameplay screen with 3DS. But here it's not being designed for at all.
Still, the actual in-game assets show a conscious decision to design for all three (3DS, Vita, PC) platforms and scale between them.
I'll get it on 3DS if the 3D is good -- 3D tends to solve any problems with the 400 x 240 resolution since it doubles to 800 x 240 and your eyes can pick out everything instead of it being jumbled into a single image.
But that depends on whether they have enough depth *and* convergence. But the chunky character models and camera angles certainly look like a great match for the 3D effect. Anyone who's played the Layton games, or Ace Attorney 5, or Layton Vs AA, in 3D, will get what I'm on about here.