Dumbledore isn't dead

(Read "Lightning-Struck Tower" first)
The first who enter in Dumbledore office after Dumbledore and Harry went out to find the Horcrux, (in the night that Dumbledore supposely dies) are McGonagall and Harry, when they get there (Dumbledore was already dead) and his painting was already there, what probably means that it was all planned for everyone to believe that Dumbledore really died.
Harry could swear that he had seen a phoenix flying to the sky directly from inside Dumbledore Tumul, that on that time was circled by fire. This can just explain Dumbledore soul going to the sky. But if you have read with attention when the fire stops, Dumbledore's body is hiden by stone and the tumul is already closed so: anyone sees Dumbledore body after the phoenix leave is body.
When Dumbledore is blasted in the tower, Harry swear that he have seen Dumbledore floting before falling. That probably means that Dumbledore landed softly.