I love Harry Potter and JKR as much as the next person, I was 11 when the first book was released so like many of us grew up with the books and films.
That was over 20 years ago and Harry Potter is still ubiquitous. Lots of shops (Primark etc) still have HP merchandise, there are adverts all the time for the studio tour, new books and computer games are still released every now and then, the films are regularly on TV and now there's going to be a remake of them.
I sometimes think they should give the marketing a rest for a year or two before the tv show is released to let us get excited about it again. Then again you have to make money while the sun shines I suppose. Will we ever reach full Harry Potter saturation?