Very good indeed. Hitchens nails it in the introduction when he writes about Orwell's lifelong determination to confront his own preconceptions by experience being at the root of his lasting value. I've always felt when reading Orwell that I wasn't in the presence of someone more intelligent or better educated, but more thoughtful and perceptive than I am, and Hitchens' comment makes it clear why that's so.
However, I think that Hitch is a little too inclined to ignore some of the discrepencies between what Orwell thought privately and what he wrote; he quotes some of Orwell's critics out of context; and there are some errors of fact.
This last one is easiest to be concise about. Hitchens' makes a huge, howling error in discussing Orwell's literary insight in his article about the weekly magazines, like "Gem" and "Magnet" published for preadolescent and adolescent boys. Orwell speculated that the stories, published under the name "Frank Richards" could hardly have been the product of one writer, given the forty-plus year run of both magazines. In order to achieve continuity, what was needed was a highly artificial, repetitive kind of style.
Hitchens claims that Orwell was proven right. But, no, he wasn't: Orwell's article was published in the April 1939 issue of "Horizon", which two issues later published a rebuttal by the writer, whose name really was Frank Richards. Furthermore, when his original article was republished in a 1945 anthology, he adds the footnote "I was quite incorrect about this." Ouch.
However, like both Orwell and Shakespeare, there is always more to praise than there is to censure.