It's well known Nintendo isn't friendly toward third-parties and it's consoles lacking support from them. It's happening with and happened with N64 and GC before as well. The reasons, according to most of third-parties, for not supporting Nintendo consoles were these:

3P Complaint: N64 - don't want to make games for it because carts are small memory/too expensive and programming for it is hard

Nintendo Answer: The GameCube, which is much easier to program for (and easier than PS2 by all accounts), has discs this time and is very powerful.

3P Complaint: PS2 is the clear market leader, discs are still too small, GameCube demographic is "kiddies" and doesn't match up with our "mature" games

Nintendo Answer: Wii, which has not only the largest install base, but has a far wider demographic than any other console, including a much higher percentage of women and people over 30. Oh and we have full-sized discs now

3P Complaint: Wii is too underpowered, can't realize our incredible vision, too hard to judge the massive market, weird controller makes it too hard to port games, online is too difficult to utilize effectively, etc"

Now, if Wii's successor is more powerful than PS3 and Xbox 360, get a decent online community and fix most of the issues people are complaining about, what third-parties this time will use as a justification to not support it?

I don't really think they need to justify not supporting it... if they don't want to, they don't have to. It's their games. And in some cases their loss.

Now for me the lack of support for wii seems a bit odd for some things... beings it's so cheap to develop for with a bigger userbase. tho I'm not the biggest fan of it, because of motion controls and dated tech. And a crappy online system.

But the previous 2 gens... Simply were stupid nintendo design decisions... the N64 cart, obv, and making a mini-DVD was assinide, when they could just put a normal size on ein and get much more space.

Not saying the PS3 PS2 isn't without flaws (difficult to program for) Xbox, RROD. My favorite gaming device is and always is the computer. But that has problems as well for profitibality reasons for companyies. But many of my favorite games are developed only for consoles. :D

They'll say

"As many of our games were on xbox 360 and PS3 this gen we would want to continue to put our games on their successors"

I also believe if priced right a PS4 and Xbox 720 may do better than a Wii 2 from launch.

Do you think Wii 2 will top GC? and what makes you think Wii 2 will sell badly? it maybe another innovative machine as if it will make us think " No way would have predicted that".

I never said Wii 2 will sell badly.

Things can't be defined as just good or bad....there is a middle ground lol

Wii 2 will top GC blindfolded......next generation might be the closest generation ever.

I say it will sell more than 40M, Iwata is  clever man, if he made people wet with 3DS he may very well shock us all with Wii 2, Super mario galaxy 3 in HD? how about Super smash bros Global apocolopase in HD.

You have basically said the Nintendo has been a generation behind sony and ms. You realize this right?

We can always fall back to: "Nintendo games are too awesome... only Nintendo games sell on Nintendo consoles.... we have no chance so we won't even try..."

IT IS TOO POWERFUL! IT WILL DOOM US ALL!!!

 what third-parties this time will use as a justification to not support it?

Says Nintendo on the console :/

It must be great to have third-party games on a Nintendo homeconsole library. You have explain it, the wrong decisions from Nintendo. If Wii = DS, then: Wii succesor = 3DS. I hope so.