Thereby shooting down any fanon conception of her as a "good" Slytherin.
(Now you know why I'm on a writing hiatus until after "Deathly Hallows" comes out!)
It's not that I have an issue with Hufflepuffs nor even really with her being one.
It's just that she, as a member of the House of Black, reknowned for putting out generations of Slytherins, was widely seen among fans as the likely sole example of a "good" Slytherin. Snape's tainted by Dumbledore's death and Slughorn is a posterboy for venality at best. Draco may be a dud as a Death Eater, but he still tried repeatedly to kill Dumbledore, even if Severus had to finally do it for him.
To me, this just underlines the "Slytherin = Evil" equation that has run through the series to date. Unless the last book has Lucius redeeming himself by switching sides and Severus being somehow loyal to Dumbledore, the message I get is that the Sorting Hat can determine that an 11-year-old child is likely to turn out to be a bad egg -- and possibly a VERY bad egg indeed.
So much for Dumbledore's assertations that "it is our choices that show what we truly are, far more than our abilities" and "it matters not what someone is born, but what they grow to be."
Given this, I'm surprised the Wizarding World doesn't set up a gas chamber in the backyard of Hogwarts to get rid of all the little snakes as soon as they're Sorted. Save everyone a whole lot of bother, now wouldn't it? "The only good Slytherin is a DEAD Slytherin" and all that.
~~ wants to throw rotten tomatoes at Rowling ~~