This is my favorite scene with the Durselys ever as they get some comeuppance. Not cheesy slapstick comeuppance but actual "you guys suck for the way you treated Harry" comeuppance.
In many ways this first book is reading like the last book in the series should. I don't know why. But they've done things like have the two ministers review the events of the previous books and had Dumbledore actually talk straight to the Durselys.
I wonder if Mrs. Dursely' s experiences as a kid with the wizarding world will ever come into play.