Nah, I think Nintendo just got lucky with the Wii. Most likely they're going to get Gamecube'd again, (as in, the system will still have high quality first party games, but will likely not sell as well as it should), this time around.
Likewise if the Wii-U is ONLY as powerful as the PS3/360, what happens in the next few years when the PS4 and the next Xbox come out? Then once again Nintendo's console will be underpowered compared to the competition, and once again third parties will move on to the more powerful console.
At this point its obvious Nintendo is just going to keep being Nintendo. They have never had good third party support since the Super Nintendo days, the N64/Gamecube/Wii all had a terrible library outside of first party titles and a select few third party exclusives. On top of that the Japanese game industry as a whole is failing and falling behind western devs.
Like most people, my view on Nintendo back in 2006 is very different to what it is now in 2012. While the Wii-U will likely be successful, I definitely don't see it being the hit the Wii was and they're just going to screw themselves over again once Sony and Microsoft come out with their next consoles in 2013.