A whole new kind of game
Capcom have cleverly made the whole point of Dead Rising that you only have a limited time inside the mall. 72 hours equates (with some very rough back-of-the-envelope maths) to only around six hours of playing. Couple this with the fact that, if you choose to, you can skip large chunks of the game by just standing around in safe areas and you can easily do a play through in a (long) evening. While it's probably possible to do everything in one play through, it isn't necessary. Even the 'Saint' achievement lets you make a few mistakes. So you can play through once doing the story missions (ignoring the survivors) then do the reverse on your second play through. You can concentrate on killing zombies. You can concentrate on killing psychos. You can do whatever you want. The fact that the game uses a generic points system to boost your skills means that if you find a particular mission too hard, you can just roam around and kill zombies, take photos or eliminate psychos until you're skilled enough to make the mission a breeze. The fact that you can pretty much pick your weapon when facing a boss means that you can tackle them your way, which does a lot to eliminate frustration. Dead Rising isn't perfect: there are some irritating bugs, and the text is too small for comfort on non-HDTV TVs. But some truly excellent achievements (probably the best collection I've seen on any 360 game so far) and a great sense of fun far outweigh these problems. Pick it up and you'll find it's one of the best value story-based games you'll ever own - just remember not to approach it as you would the competition.