Alright here are my predictions so far. The Griffindor sword in dumbledore's is a horcruxe. that is why voldemort came back to see him when he was "trying to get a job teaching." I am not to sure about snape I still think that if dumbledore trusted him that he may still be good. I realize that he is an expert in Occlumency but is it possible that he is being control by voldemort? it just didn't seem right that he would still be loyal to voldemort after everything he did for the order.