Just been to see it with DD1. And loved it. To be fair, I've loved (nearly) everything Simon Pegg has been in (not so much Run, Fatboy, Run) and was hoping for the same mix of sci-fi/fantasy twist in a funny film.
It was slower to get going than Sean of the Dead, but then you didn't know exactly what was coming.
I thought the ending with Bill Nighy particularly amusing.