I understood at least five years ago that the series is never going to be completed. Fans will be milked _a la_ Christopher Tolkien ("look, we found a few manuscripted pages that seems to be a draft for a chapter", $20 for 100 pages, hardcover and illustrated), but I won't spend another cent in any Martin book until "Dreams of Spring" is published. And it will never happen.

Also, Martin is 100% against fan fiction, and the main reason is $$$ (he barely conceals it). He would never allow anyone to work on the series unless a load of money is deposited in his bank account. Good for him if he gets it!