On a whim I stopped by George R. R. Martin’s site, and discovered that At Long Last, after untold decades of feverish expectations, A Feast for Crows is moving into production. For fans of the fantasy genre, this is indeed big news, as the third book in the series (Feast is the fourth) was published in October of 2000.
As for when it will hit the shelves—as near as I can tell, sometime between late July and December of this year. Use the intervening time to read the rest of the series.