Basically, the problem with Orwell is that linguistic relativity isn't real - language doesn't act in the way he thinks it does. If some word becomes impossible to say, that concept doesn't vanish from the air. Take the word "faggot", now largely considered impolite in most company. Someone who wants to deride a man for being effeminate could replace it with a limp wrist gesture, a finger in the hole-gesture, a combination of "Does he..." and a jerk off motion, etc. The underlying concept being discussed does not change, but the expression does.
Newspeak is predicated on, essentially, the "strong" version of the Sapir-Whorf hypothesis: that is, the idea that if you lack a word for a concept, you can't intellectually apprehend it. I don't think that actually games out, and he based his book on a fundamental cart-horse displacement.
I think the best parts of the books are when he gets into the culture of the Party, and I also liked how much of a deranged pervert Winston was.
