All publishers looking to do kids games or mainstream multimillion sellers should certainly make 3DS their priority as it's basically the only platform where those efforts have been really successful for 3rd parties. At least amoung dedicated game systems, obviously smart devices hit those same demographics too and often even better depending on the title.and of course 3DS is the only safe place for the whole videogame industry, the only platform which can guarantee strong sales for every titles.
all publishers should move on it
Vita and consoles are fine for their specific niches (otaku fanservice and Sony subsidized hunting games on Vita, AAA global hits and PS3 ports on PS4, Nintendo family fare on Wii U) but they're still niches. Level 5's been making the right calls on platforms for their games the past several years I think. Safe and smart.