This Ars Technica
article is good:
As a fantasy literature enthusiast, I am disappointed by Rowling's unwillingness to achieve a reasonable compromise with Ark. She clearly saw value in his work and could have even collaborated with him instead of trying to create her own future lexicon from scratch. Inventive borrowing is the lifeblood of the fantasy genre and her attitude on the subject reflects some hypocrisy.
I side with Orson Scott Card
. Like him, I've found Rowling to be a disappointment in her post-Harry career; first the Dumbledore debacle, now this.