This says it all for me. Straight from the man.
Miyamoto explained to shareholders at their most recent meeting that higher-rate visuals on the new console have required around double the effort of Wii games:
When it comes to the scale of software development, Wii U with HD graphics requires about twice the human resources than before.
So that basically means that dev's on the Wii now need twice as much time if not even MORE for that Wii U. Simply because Miyamoto has more resources and is closer to the powers that be and it still takes 2x as long for the master game maker. Well then you know it's very bad for the others trying to make games when the guy with 30 years experience says it's a pain in his ass.