if with their next system they manage to integrate a cross system thing merging their handhelds and consoles, then they will have amazing 3rd party support. think of it this way- currently the 3DS has awesome overall 3rd party support. The Wii U very mediocre, however I think a lot of that can be blamed for the risky attempts with the tablet controller and maybe some ill will from the Wii generation
so it's a toss up
like I say, if their next system connects handhelds and consoles to some degree then without a doubt they will acquire a huge number of the third party developers support as many companies get some nice sales from the Nintendo handhelds. if it is just another seperated individual thing (handhelds and consoles) then I am not certain and it probably won't be the case
too early to say. the software developers will decide once they see how difficult (or easy) it is to work with the specs and platform so obviously it's quite difficult to say this early
