Evanna Lynch is Sorted; What House is she in?

Pottermore has at least 23,000 of its beta members into Pottermore, and while none of us have received our e-mails, someone special has. Evanna Lynch--Luna Lovegood in the Potter films--received her "Welcome" e-mail and made her way to the "Sorting Hat" chapter in Potter, Tweeting little teasers to her followers, stating that Ollivander was a Ravenclaw. She then Tweeted that she had been Sorted, but that the result was not Ravenclaw, the House she had been hoping for. Instead, Evanna was Sorted into Gryffindor. What does this say about Jo's idea of Sorting versus the fan's ideas?