Re: A Song of Ice and Fire SPOILER THREAD (srsly spoilers from all the books ITT)
For what it's worth Roy Dotrice the guy who does the audiobooks for Martin said in an interview in November in regards to the show and books "They've done three, so that's two more to go and George tells me the next one is nearly ready".
About 20 seconds in if you want to hear it.
Whether that means anything or not who knows. It is interesting to note though that at the GOT Season 3 premiere in MArch Liam Cunningham claimed Martin told him WOW was "half done". Presumably, Martin would have made good progress in the 8 months that followed. So, maybe there is something to it and the book is not far off.
From what I can recall from reading the books and other forums, he is supposedly a high-born bastard (hence the name Waters) who has Targaryen features and could possibly be a Blackfyre that Cersei made Master of Ships but around the time of her arrest he took off and supposedly is allied with the Tyrells.