Today they launched a new website called The Maester's Path. Each week from now to the start of April new puzzles will be unveiled which, when solved, will lead to rewards. The first puzzle revolves around the 'scents' of parts of Westeros (and beyond), a reference to the promotional boxes of scents sent out last week to various critics and bloggers. Westeros.org has handily collected all the symbols together here. What reward do you get? The first full scene from the series :-)
In related news, all four ebooks of the series should now be available in the UK from Voyager, and the TV tie-in edition of the first book should be properly unveiled in the next couple of weeks or so.