It looks like IGA might be branching out just a bit in the future -- still in 2D, but he hinted that he had something new on the way. Something ... maybe not on the DS. "This time, I announced a DS title, but I definitely want to grow the franchise. It's something I'm really focused on. You guys will probably be hearing something from me."
It sounds like whatever the project is, it'll still be the "Igavania" style we know, since according to IGA, the more linear Rondo of Blood PSP port was good, but "not something that I can jump up and down and enjoy like I do with the DS titles."