Continuity mistake: When the Suburban is T-boned, it is replaced with an older 92-94 Suburban with the front end of a newer 00-04 Suburban installed in place of the older front end. Older model 6 spoke wheels are installed instead of the 00-04 wheels shown in previous scenes. In one of the shots towards the end of the sequence, a completely different 96-99 suburban is shown rolling over with five spoke wheels, and the scene is mirrored.
Continuity mistake: Early on a pallet is leaning against a building with nothing next to it as two star members are backing up shooting at zombies. About eight seconds later you see an aluminum tube standing in front of that pallet. It then comes and goes. (00:15:00)
Character mistake: Jill states that a 5 kiloton nuclear weapon will sanitise the city, however, such a yield is far too small to destroy the city. (00:42:00)
Answer: First, the T-virus affects humans and dogs differently - zombie dogs look like they've been skinned, but zombie humans just look dead. Second, there's little evidence that human senses have been dimmed, it's just that zombies are stupider without higher brain functions (explained in the first movie) and are slower because they conserve energy for actual attacks, not moving. Dogs are much more efficient predators than humans and don't need to slow down as much because a few bites will take down prey.
Phoenix