however how meaningful is this to the third party publishers if MOST best selling games on Wii U are only nintendo games?
At this point it looks like the general consensus is to get a Nintendo console for only Nintendo games and either a Sony or Microsoft console for everything else. And Nintendo alone is to blame for that perception. Wii U launched with no exciting games and it took very long for any must have games to be released. Not to mention Nintendo still hasn't entirely delivered on its promises with the Wii U GamePad. By now people already lost interest and this was greatly reflected in the media. The best opinion pieces defending the Wii U say things like "it's the best place to play Nintendo games" and that's exactly what the Wii U is. Nothing more, hopefully nothing less.