As someone really hyped for Madworld and tried to like it more because of that, I can say now looking back at it that it wasn't very good game. I liked it but it was essentially the same few minutes of fun over and over again for four hours, then the game ends. Still had really nice style (with music that really set the mood) and enjoyable boss battles.
I forgot who made the comparison, but someone likened it to Dead Rising more than a beat em up and I'd agree. But Dead Rising had you doing other things while racking up points and killing zombies. MadWorld was just scoring high, and it didn't give you a reason to care about that score.
And if someone wants to blame third party for not giving a shit about the wii, blame Nintendo. If they made the hardware comparable to the other two, then the Wii would get scraps like the Gamecube did last gen. Now it doesn't even get scraps from the PSP/PS2 (and vice versa). The audience for "hardcore" wii games are on the Xbox 360, and devs are able to make the same game for that, the PS3, and PC.