I read the book at a bit of a run but without being utterly wowed by it, which I guess makes it an easy reading page turner.
As a book it reminds me of two films, the early Ben Stiller classic "There's something about Mary" and Simon Pegg's "Shawn of the Dead."
In common with Ben Stiller's grosser film comedies, it has moments where you think "I can't believe they just did that" There is a scene or motif that makes you smile or laugh while you cringe at the imagery. The effort to deliver a visceral shock with a wry grin can be a little hit and miss at times. On the whole it works but it lacks the subtle satire of the discworld novels. This is a book that drops its trousers and waves its humour in the reader's face.
In common with "Shawn of the Dead" it has a cast of characters who on the whole are the architects of their own demise through over developed stupidity glands. That can work, but it means the book's few attempts at poignancy don't quite work as well as they might. It takes a lot of internal reflections by characters on the well concealed virtues of their lost family members before we are exposed to the grieving scene, but this amounts to telling us the people are entitled to grieve rather than showing us convincingly why they grieve.
OK I hear you say, it's a comedy not bloody Hamlet cut some slack here and this is true. But even in comedy I felt there should be more consistency of purpose or smoothness of transition between mortal grisly peril and the amusing sex obsessions that seem to infect everybody (not just the crazed animal zombies) when facing a near death experience.
The other points of plotting concern are the mismatch between the characters' priorities and the scale of the cataclysm that has overwhelmed the UK. When not musing about "oh this is going to be bad for the economy" or "when can I rub my face in her breasts" the central thrust of the story is the protaganists' desire to reveal in a world exclusive scoop the conspiracy story behind the bovine apocalypse. To my mind this was like watching the passengers painstakingly fretting about the positioning of the deckchairs on R.M.S.Titanic. It just didn't seem to me like anything anybody would have cared about. But then I am not a journalist by profession while the author, Michael Logan is, so he is probably better placed than I to judge what thoughts would run through a journalist's mind as a government triggered Ragnorak drew near.
So, if I were to pick two weaknesses which each knocked a star of my enjoyment factor, it would be
a) the slightly jolting gear changes of plot/pace/motivation which, for me at least, created discontinuity.
b) the reliance of the humour on shock factor. It felt to me a bit that if we're not sure its funny enough let's add extra blood and gloopy bits, take off more clothes, and throw in a bit of bestiality or cannibalism.
But setting aside the agonising over why I am not giving it 5 stars or 4 stars, I am giving it 3 and that means, as it says on the tin, I liked it. It's a good read, not too taxing but with some entertaining images.
I have to confess my favourite character was the principal villain, Alistair Brown. I'm a sucker for a smooth talking smarmy murderer, but then maybe that's just my grimdark roots showing through.