I wouldn't trust the comments here, mainly because a lot already decided they hate Dead Rising and love Madworld based solely on trailers. That's a disservice to Capcom, Sega, and Platinum, as it ignores any actual effort or talent. It only goes by appearance*, which considering the Wii was designed to go AWAY from that, is also a disservice to Nintendo.
In terms of actual content, if you like brawlers and black humor, then Madworld would be better. If you prefer more action and exploring, than Dead Rising, since it fixes the control of the 360 version and has more saves.
So it's really down to the type of game you want.
* Note I wrote "only", as in appearance was all you had to go by when you judged from the trailers.
A flashy-first game is awesome when it comes out. A great-first game is awesome forever.
Plus, just for the hell of it: Kelly Brook at the 2008 BAFTAs
