I feel certain that Jon Snow is TPTWP, and here is why...assuming that Jon Snow is the son of Rhaegar and Lyanna Stark...
According to prophesy, Azor Ahai is to be reborn again as The Prince that was Promised to challenge the Others/White Walkers. This will occur after a long summer (which is about to end now), when an evil, cold darkness descends upon the world (how many times has it been drilled into our heads that winter is coming, and it is going to be BAD!!!) The Prince that was Promised, wielding Lightbringer once again (Longclaw will be the reincarnation of Lightbringer IMO), will stand against the Others (apparently, since he is Lord Commander of The Night's Watch) and if he fails, the world fails with him (nothing happening in The Seven Kingdoms means anything if the Others take over during winter.)
Longclaw is said to be Valyrian steel, and Valyrian Steel is said to be a magical alloy invented in Valyria made special by spells and magic. With the re-occurrence of the dragons, I see many possibilities as far as magic is concerned, and I see the dragons as the key to re-creating Lightbringer.
I also feel that Jon, Dany, and Aegon(son of Rhaegar) are the three heads of the dragon, and they will eventually ride the three dragons. Also, Jon is "The Song Of Ice And Fire" given his parents are Rhaegar(Fire) and Lyanna(Ice).
These are just my opinions…please discuss…
ETA: It's amazing how much my views have changed since joining this forum. I had only read the first book and spoliers at this point.
Edited by Lady Tippy Wolfsbane, 11 June 2012 - 07:26 PM.