My theory!
I believe Dumbledore can't be dead! Everyone who was hit with the Avada Kevadra spell has just slumped down dead. That's it. Dumbledore flew! HE FLEW! So:
You know Snape is not a bad guy because he obviously didn't use the killing curse.
In the first book, Dumbledore says something along the lines of "Death is but the next greatest adventure". Why would someone who believed that plead for his life? Snape hesitated, maybe he was scared to use the spell and Dumbledore was just telling him to do it.
You realize that after Dumbledore is "killed", you never hear of the body after that? His body was supposedly wrapped in the star cloak and then put into the white tombstone where it burst into flames!
What happened to his wand! Anyone other than me notice that Rowling doesn't mention anything relating to Dumbledore's wand after he got shot with that spell?
"Faithful servants". Malfoy doesn't kill Dumbledore; Snape (I believe) also doesn't kill Dumbledore. There ya go.
Thanks to my friend Ribbit (that's her nickname not an account) for most of these ideas. I owe ya one!
Bye all!