First off, it's spelled STALE. "Stell" is not a word.
Secondly, Super Paper Mario (2D/3D flipping), Super Mario Galaxy (planetoid levels/gravity physics), NSMB Wii (4 player co-op for a platformer), Skyward Sword (motion controlled swordplay done right) might want to have a word with the whole "lack of innovation" thing, not to even mention Wii Sports, Wii Fit, etc.
And if you want to point to ANYONE for "putting out the same thing", "lacking innovation", and "growing stale", why not start with:
Sony
Microsoft
Epic
EA
Activision
Sega
Konami
Capcom
Square-Enix
2K Games
Ubisoft
or any of the endless number of developers whose games they regularly publish.
Pointing to Nintendo and accusing them of milking franchises and doing nothing new, kind of falls spectacularly short of the mark and comes off and incredibly disingenuous when all the (JUST RECENT) games that people love to play, IE Gears of War, God of War, Halo, Assassin's Creed, Bioshock, Tomb Raider, Call of Duty, Madden, etc. etc. etc., are all pretty much the exact same thing every iteration. Sure, the new Tomb Raider is "different", if by "different" you mean "copying what Uncharted does to try and seem modern and relevant".
I'm just saying. Pot calling kettle black. If ANYONE has been doing even the tiniest bit of innovation over the last many years, it's been Nintendo, and not much of anyone else. Yes yes, Sony had it's Wiimote Nunchuck that they've largely abandoned. Microsoft had their Kinect, which while LESS a blatant ripoff by being "controller free", was also notorious for just not working that well, and quite frankly most people want AT LEAST some kind of wand to wave around, instead of flailing around sans-controller. And for all of that, both were merely peripherals which continued to be largely ignored when it came to their actual big game releases.
The GamePad, at least, is rather innovative in it's approach to a home console spectrum.
So regardless, calling Nintendo out for making more of their old franchises and "not being innovative" is rather silly considering the state of the industry as a whole.