Changing Houses

[JoAnna]

No: HPFGUIDX 93275

>   (Kimberly's comments)
>>   Now the question is, did Dumbledore know this before this 
conversation or not.     Just after that you have the instance where 
Dumbledore shows Harry Godric's sword that Harry pulled from The 
Sorting Hat, thereby attempting to prove to Harry that he was indeed 
placed correctly.>>


My guess would be that Dumbledore did know - after all, the Sorting 
Hat does live in DD's office, and I imagine that DD has 
conversations with it from time to time.  Perhaps DD conversed with 
the Hat after the sorting to find how/why it sorted Harry into 
Gryffindor.