Why are you citing MadWorld, No More Heroes and Red Steel as cornerstones of Wii gaming? Those games are built specifically for the so-called "hardcore" audience on Wii, but they don't come up to the standards of similar games on HD systems. (And honestly, I think most people think they look boring and stupid.)
The real fun on Wii is Wii Sports, Mario Kart, Smash Bros, Mario Galaxy, WarioWare... And yes, those games are a ton of fun.
And then think of DS+PSP versus GBA. No contest there. And then throw in Rock Band for this gen.
I think this gen basically crushes last gen in terms of fun. In fact, I'd say it kind of reveals how standardized and boring last gen was. I didn't even realize that I had one foot out the door until games like Wii Sports, Mario Galaxy and Rock Band.
"[Our former customers] are unable to find software which they WANT to play."
"The way to solve this problem lies in how to communicate what kind of games [they CAN play]."
Satoru Iwata, Nintendo President. Only slightly paraphrased.