Nice post, Julie.
I've always thought that fantasy needs more internal consistency, not less. If you're going to make the leap that purple unicorns are our world's overlords, it's like you've used up the quota of disbelief. That's all you get. I've also heard it described as "you get one big lie," although to be fair, I've sometimes seen two work out. Not three.
Anyway, I'd like to see a distinction between plot holes and world-building holes because they're really two different things. For instance, I've always had problems with Harry Potter, but it's always been with the world-building. For instance, she's got abused kids going to Hogwarts, and it's pretty clear that all Hogwarts will do is provide them with a haven for ten months of the year. They've got to go home in the summer. And yet, there's never a case of muggle parents forcing their kids to fix the stock market or similar so they can get a leg up. Seriously? That would totally be an ongoing problem.
However, this has nothing to do with the actual plot. I always thought the books were well-plotted.
I've often wondered why we don't distinguish between the two.
