Well, it has bothered me that Rowling’s protagonists are so offhandedly dismissive (or patronizing) toward mundanes. I think she’s doing it intentionally, though…and I think it’s going to have more of a deal made of it later on.
And don’t start with Pratchett’s first books. The series is only loosely chronological, and even that’s assuming a cohesive storyline. 
I give people Small Gods and, if I think they can handle it, Men at Arms. Lords and Ladies was my first, and it makes you fall in love with the world, but it’s not the best way to start, I think…
I thank you for the kind words, my feline friend. For the record, I’m male–although my posting style and username have been known to cause others some uncertainty on the point. It does not trouble me…unless, of course, it denies me the affectionate regard of another Doper. 
Ahem. Now, as to the idea of Pratchett satirizing Potter, I could see it happening, but only in a small way. A brief aside, perhaps something like rjung’s excellent bit on sports and broomsticks at the UU, would be quite amusing. I don’t see making an entire subplot out of it, however. A simple nod, in pTerry’s inimitable style, to a fellow fantasy author would not be out of place. If I were Rowling, I would be rather flattered by it. I doubt that she would make legal trouble over it, at any rate–I haven’t heard any fuss over Neverwinter Nights: Shadows of Undrentide, which contains at least one mildy humorous Potter reference.