During a fictional series of Big Brother, a zombie outbreak occurs, but the house-mates are unaware of the impending doom outside of the Big Brother House.
While I recognised the actress who played Alex and the guy who played Patrick, I had to go to the IMDb to get the "where" (she played the medic in Resident Evil and he was in Death at a Funeral) no one in this show was familiar to me. I don't watch any Big Brother, much less the UK version, so I suppose that most of the jokes and cameos simply went over my head, the rest of the series was easily grasped by an American like myself.
The visual influences on the film are easily recognized: it's the 28 movies' cinematography mixed with the Shaun of the Dead make-up on the Dawn of the Dead remake's running zombies while stealing two set pieces from the Romero Day of the Dead (Rhodes' death and Torrez's beheading.) It's understandable; as far as I'm concerned, those are two of the best deaths in zombie cinema. The effects were fantastic and the cinematography could have been less jumpy, but it looked good.
While running zombies are scarier, they lessen the impact of the message of a well-written allegory. They were perfect for Dawn of the Dead because, let's face it: it lacked the heart of the original. In this series (released on British DVD November 3 -- no news on an American date and thankfully no news on an American remake) the runners provide more tension for the ending, otherwise the shamblers probably would have sufficed.
Charlie Brooker's script (lauded by Simon Pegg in his MySpace blog at: http://blog.myspace.com/index.cfm?fuseaction=blog.view&friendID=213643855&blogID=446170305) was fantastic. I thought it was a bit slow in the beginning, but it gets much better as it progresses and the ending is incredibly intense. As an allegory, it's absolutely wonderful and as a basic idea, I thought it was brilliant.
Overall: this is seriously one of the top ten best zombie flicks ever if for nothing other than the last episode. So great. If you can get your hands on it, I highly recommend it!