I am on a strict Potter embargo while I decide for myself what my opinion is. Right now there are simply too many people ready to decry or exalt the entire series. I won't say anything other than it's provided me with many hours worth of enjoyment and contemplation that has been well worth the price of admission. What more can one ask for than that which occupies the mind and heart? And, at the risk of sounding like a raving Potterite, it does rankle me that you have read McArdle's article and even quoted it, but reveal that you only have the movies--stylish, anglophilic and telegraphed as they are--to go on. I think you must soon make the time, wouldn't you say?
A challenge then, Dan? Tell me why the Potter books work, instead of their inconsistencies. What does Rowling do right as opposed to what she does wrong? I daresay you would enjoy yourself, even if you were busy falling through plotholes. I might not be happy with your answer either. But such is life!
Worst case scenario: you spend more time reading than perhaps you should.
The McArdle article does seem to have that effect on raving Potterites, and frankly I don't see how the books could counter her criticism. It's not like the elitist critiques you get from the likes of Harold Bloom, and it was the novelty and obvious truism of the criticism -- not that fact that it was down on the books -- that interested me in that article. Not that the world needs more people praising Harry Potter; for me the disagreement is inherently more interesting.
I'm planning to read the Harry Potter books, though it seems like it was the mass phenomenon and not the literary value of the books themselves that was the real treasure here. If I had my way I'd watch all the movies before reading the books -- more surprises that way -- but I know that with the last book out I have only a month or two before dodging spoilers becomes impossible.