Difficult to provide an interesting review of a book of expert literary criticism, but since I'm the only person on this site to have read it (give me a medal), I think I should at least try. Ok, here we go, get ready for this...
It was good.
What, I have to write more than that? Okay, I mean, I wouldn't read it unless you've gone through at least most of Orwell's bibliography, but if you do that and are interested in this sort of thing it is indeed a very good wholesale analysis of (roughly) the effect that Orwell's narrative selections had on the work he produced. Far more readable than your average work of literary criticism, especially any of mine.