By the way I am going to talk about the ending, so if you haven't seen this yet and still plan to then for your own sake stop reading now.
Anyway, I had several gripes with this movie.
1) The human-to-zombie transformation seemed to vary in length depending upon who was infected. When Don became infected (gripe number two), we had to watch almost a full minute of him staggering around the room with foam coming out of his mouth before he actually became "one of them". Yet most of the other people who were bitten or spit on or whatever almost instantly turned into zombies.
2) Don kissing his wife and turned into a zombie. Thinking about this more, I suppose it didn't occur to him that she was a carrier. I don't think anyone knew except the General and Scarlet, so it makes a little bit of sense that no guards would have tried to stop him from reaching her, after all she was his wife and he had that fancy little card that let him go anywhere in Sector 1. What really gets me is how Scarlet didn't immediately think "Well shit, this woman is a carrier maybe we should either A) kill her immediately or B) lock her in the room AND post guards that know enough not to let anyone in (especially Don)".
3) A lot of scenes bordered on hilarious unless you stopped to think and place yourself within them (use your imagination kids). When the zombies chased someone they hauled ass and didn't care what it looked like, which coincidentally looked hilarious. That said, placing myself in that situation I would have been scared as shit and probably wouldn't have been very concerned about how stupid the zombies that were chasing me looked. The subway scene at the end looked like an episode of Ghost Hunters (yuck), but again "realism"; that would be pretty scary if you stop to think that A) it is pitch black and B) they were walking over a bunch of corpses.
4) The ending was a little too ambigious. As heartless as it sounds, I don't really feel like escaping with (the now infected) Andy to France was such a good idea. The last scene leads me to believe that somehow Andy transmitted the disease to someone and the whole thing started over again. That, or Zombies broke through the Chunnel (which would just be stupid on the part of the military, I mean honestly just collapse it).
5) The violence is (at times) excessive. Maybe it was realistic, but I'm pretty sure if I was in that room with Don and Alice I would be more concerned with GTFO than watching him pop her eyeballs (yuck).
The soundtrack was so excellent that I am listening to it right now.
Top 3 favorite scenes from the movie.
1) The firebombing of London.
2) When Flynn chops down like 50 zombies with his helicopter.
3) When Doyle shoots the zombie that is about to bite Andy.