To be fair, the 3DS does have two of the heaviest hitters in Japanese gaming coming up at some point this year; perhaps they're waiting for the announcement of the release date of MH4 and Pokemon, and then will set their own plans accordingly. It's a bit too early for any of the Japanese companies to be announcing their holiday lineups, and the summer is going to be dominated by Nintendo stuff (Mario & Luigi, Mario Golf, DKCR 3D)/Monster Hunter (although there might probably a few 100k games that haven't been announced yet). Plus, the 3DS in the West has a very good lineup, and the base is going to build a lot with both Animal Crossing and Pokemon coming up this year. The 3DS is going to receive a lot of support in its lifetime.
I don't doubt the 3DS will be very well supported.
My main question is volume of titles as opposed to the impact of those that exist.
Nintendo basically has tons of giant flagship franchises from first and third party on the platform, but I guess my question can be summed up as "Has the same polarization that's effected console gaming the West notably impacted the 3DS in Japan, causing a reduction of titles in favor of only making a company's biggest handheld titles on the platform, while reallocating most resources that made smaller handheld titles elsewhere?"
Square Enix is kind of an interesting case study since they had a large volume of handheld titles relative to many other publishers, but it seems to be shrinking. Is that a reality, or a factor of announcement timing? I think it's an open question, but one that's slowly becoming less open.