Thanks to the splendid Maureen Ryan of the Huffington Post, she has shared her post and recording from her hour+-long interview with George R.R. Martin at Chicon 7 , this year’s Worldcon. The post provides a great synopsis and guide to the full interview, and it’s much recommended. Some good stuff in there—anecdotes about writing “Blackwater”, the role of prophecy on the TV show as compared to the novels, and more—that you should really make time to listen to.
One note on the Mance Rayder’s age query: GRRM’s forgotten that the ten-years-before-AGoT Mance Rayder is described as a “young black brother” in the very chapter in which he’s introduced in A Storm of Swords.