Quite a lot bigger than the previous two. I wonder whether the success of the books caught up here and made Rowing write so much more. Right now, after a long description of the Quidditch World Championship, we finally seem to start heading towards the actual story.
It's written well, mind you, and it does indulge the reader into the magical world, but the other books seem much more focussed on the story without so much background.
It might be necessary for the story which is to unfold though. We'll see.