Orwell doesn't actually have a lot to say about the book, although as he notes, a lot depends on what translation you've got. Various translation are quite different.
I really wish there were a way to force otherwise decent conservatives to read Main Kampf to see how much of the modern conservative movement seems to be lifted right from its pages. It literally seems like there is a boiler room operation where Mein Kampf is carefully written into conservative talking points.
The strategy is crafty yet simple - first they lie about what Hitler said, then they say what Hitler said. For instance, Glenn Beck says that "social justice" was promoted by the Nazis (which is a lie), but in Mein Kampf Hitler says it is a liberal Jewish conspiracy.
With infinite shrewdness he (the Jew) fans the need for social justice, somehow slumbering in every Aryan man, into hatred against those who have been better favored by fortune, ..... He establishes the Marxist doctrine. (Mein Kampf p349)
See? If you listen to Jonah Goldberg or Glenn Beck you end up embracing Mein Kamf and quoting Nazi propaganda, because they are quoting Hitler. Also notice how Hitler is accusing his opponents of envy? The Nazis often accused their opposition of "envy," and so did Romney. Of course the Nazis promised to save the nation from Socialist "class warfare," and that's another big selling point for the GOP. The average conservative is embracing "fascism disguised as antifascism."
Mein Kampf is an interesting read. The racism is quite thick at times, but after the last 8 years of attacks on Obama, Mein Kampf has lost much of its shock value,. The sections about propaganda are quite lucid, and I think that much of this was written by Goebbels and the rest of the gang when they were all under house arrest after the beer hall putsch.