Amazon is lying to you! Check that e-mail carefully and I think you will find that it refers to a rerelease of the TPBs.
Feast for Crows is going to be out in hardback in November.
I would certainly argue that the series would support a deep reading for meaning, but I would concede that it probably lies at deeper and more profound level than allegory through the characters.
On the other hand, I also have a pretty high tolerance for the characters. I think they achieve a lot of nobility in situations that require a great deal of very basic strength and action. When survival is at the premium that it is in the game of thrones your moral parameters are going to be distinctly different.
In particular I like that the basic flaws of the characters often serve to drive their primal noble qualities. I don't know who can be held up as a hero in fantasy in general, but within the Song of Fire and Ice I think a good place to start looking for it in terms of allegory is with the seven.
Many of the qualities that make Cersei so difficult, for instance, are qualities that certainly do speak to her attributes and fervent desire to be a strong and protective mother. On the flipside of that equation most of the flaws of Caetlyn, an otherwise admirable person, are the manifestations of that exact same desire.
In a world where magic and religion appear to be gaining in strength and relevance, I find it fascinating that the Seven are having at once the least prominent and, to my eyes at least, the most profound affect.