Ok, I read a magazine with some clues in it, and they suggested that R.A.B was maybe Regulas Black, Sirius's brother who was killed a few days after fleeing Voldemort. Also, they said to keep an eye out for minor characters playing bigger roles, like the barman of the hog's head (I just realized that he is Aberforth Dumbledore, Albus Dumbledore's brother who was convicted of doing charms on goats). If you read in Book 5, during the first D.A. meeting there, Harry notices the long gray beard.."vaguely familiar"... They also mention him later on.
I also read a poll on the web that says that a lot of people are thinking that Harry dies in book 7...like, self-sacrifice to save his friends...that would really stink, but wouldn't that hold true with Trelawny's predictions of early and gruesome death? I know that she's not often right, but hey, in book 6, she mentioned to Harry how she felt a sense of doom coming ever closer, when she did the tarot cards she got the lightening over a tower....the dark mark over the astronomy tower, where the person was killed?
hmmm....
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