@drwitch I've just read it. I enjoyed it, but I agree with the point made by many reviewers, that it should have ended about 50 pages sooner than it did.
SPOILERS
Julia's learning to hate Big Brother made a neat and compelling counterpoint to the original Winston ending. I didn't see the need at all to ramble off into Julia escaping the regime, and the ending suggesting one corrupt regime would be replaced by another was weak and predictable; the meeting with Big Brother was an anti-climax. It was as if some so-so fan fiction sequel had been tacked onto the end of a decent novel.
That aside, I liked the backstory/alternative agenda that was created for Julia. Making her an agent of the Thought Police was a good idea; and I liked the idea that this served her no purpose in the end; her 'mission' was revealed to be no more than petty office politics and she was discarded once her purpose had been served - this seemed consistent with Orwell's view of the regime.
The exploration of rural Oceania was interesting. I was reminded of the rural famines in China following the 'Great Leap Forward'. Had Orwell lived to see it, I think the Chinese Cultural Revolution would have been of enormous interest to him and something he would have drawn on as a writer; so this section of 'Julia' felt very right.
I felt Julia's overall contempt for Winston was really an echo of contempt for the superficial way in which Orwell drew Julia's character originally - a way of saying 'there is far more to women than this'.
I'll probably have more thoughts on this but I only finished reading it yesterday.