My quick impressions after only completing the first four story missions:
They use a lot of tricks to make it seem that there are more zombies than they can fit on the screen at a time:
Zombies fade into view as you approach them like the scenery in San Francisco Rush. Very odd since there's no fog in the mall.. just magically materializing zombies. And they also pop into existence when you look away. So when you've just got done clearing a path to lead some civvies through you'll turn around and the zombies you just slaughtered will all be back. And hungry.
Enemy AI is practically non-existent.. but it was so on the X360 as well.
"Waggle" control is problematic. I'm still trying to figure out how to use secondary weapons on stunned zombies, but that's definately part of the fun of the game: trying to kill zombies in different ways with everything you can pick up in the mall.
Cut scenes which on the 360 were realtime rendered are now all pre-rendered clips from the 360. This means that the level of detail in the character models is slightly higher during cut scenes, and you will always be seen wearing your initial leather jacket outfit instead of whatever other flashy duds you've grabbed in the meantime.
I am very much missing having the camera. Seems strange to play the part of a photo-journalist and never take any pictures.
There is no bounding box when aiming, so if you pause to shoot something and want to adjust your view you have to use the thumb stick to aim the camera, then aim with your cross-hair. (I.e. you cannot move the camera by pointing towards the edge of the screen, which is what I've become used to in Wii FPS.) Oh, and I had to go into options and flip the horizontal while aiming because I found myself constantly pointing the camera at the floor when I wanted to aim up.
Really - the development team should have spent some time playing Godfather: The Black Hand Edition. That's the gold standard of 3rd person Wii controls, and everybody could learn from it. It handles close combat in a visceral and fun way and gunfights in a seamless and simple way as well. Dead Rising just feels clunky and awkward. I'll keep playing in hopes it will prove me wrong. There's civilians to rescue and zombies to slaughter.. so many zombies to slaughter.