Gamers who have been clamouring for adult content for Nintendo's Wii are to be sorely disappointed. MadWorld is as juvenile a videogame as Barbie's Horse Adventures. Of course, juvenile doesn't necessarily mean that it's in any way suitable for children. Quite the opposite, in fact. After all, Barbie never got to dip her pony into a flaming oil drum before ramming it onto a spiked wall. Eyes first. Repeatedly.