It is a good overview of British cuisine but an encyclopedia?... It's good but that's pushing it. It could be a better and a more exhaustive tome if it addressed regional cooking in a more comprehensive manner but that would probably push it to 1000+ pages rather than the modest 512.;^) All that being said I like having it on the shelf and if I want a recipe for bubble and squeak, colcannon, steak and kidney pie, or figgy pudding it's got it.
Update edit(1/8/11): I find myself going to this book more often than not, just to find another tasty recipe to try. It gets used a lot. I would buy it again.