A belated holiday gift from a very busy George R.R. Martin: a new chapter from The Winds of Winter. In this case, it’s the first Arianne Martell chapter from the novel, picking up from where A Dance with Dragons left off. Some interesting details, but spoilery (of course). You can read it at Martin’s official site, via the Ice and Fire Sample page.
[EDIT: Ah, in fact this is a brand new chapter that precedes the one GRRM has read], but lets just say a lot of details either missed being supplied in the reports, or have been added as he’s worked on the chapter.