Short answer? No official date has been set yet.

A Dance with Dragons is the title of the next book in A Song of Ice and Fire. It's also Book 5 of the series from author George R. R. Martin. Believe it or not, the last two statements weren't always interchangeable. The first edition A Clash of Kings claimed that ADWD would be the third book in the series. Obviously, that didn't happen. Then for a while it seemed that ADWD would directly follow A Storm of Swords. When the time came, though, we received A Feast of Crows and--wouldn't you know it--that book, too, promised A Dance with Dragons as the next title. Either ADWD is the book that GRRM wants to write best or it's the one he least wants to write.

If you're anything like me, it doesn't matter what the title is, so long as GRRM delivers another story worthy of the world of Westeros. The question, however--or as the case is here, the question that is most frequently asked--is when will the next Ice and Fire book be released?

Here's the long speculative answer. On May 29, 2005, GRRM announced on his Official Website that he had split the narrative of what would have been the fourth novel into two separate books. Half the story would be told in A Feast for Crows and the rest would be pushed back into A Dance with Dragons. This move meant that a bulk of ADWD would already be written or, in GRRM's words, ADWD would be half-done.

On January 24, 2006, GRRM's site gave the first major update on ADWD in a while. At this point (following several months of promoting AFFC), he's completed twenty-two chapters in 542 manuscript pages, plus another 100 to 150 pages of partial chapters. He expects the book to be between 1200 and 1300 manuscript pages. These numbers confirm a 50% completion rate.

Will A Dance with Dragons be released in 2006? I think GRRM has expressed a hope for that. If he completes the manuscript by May of this year, a late 2006 publication seems possible, assuming ADWD is produced and released in the same timeframe as AFFC (which is by no means a safe assumption). Then again, GRRM reported in January 2005 that he had written 1300 manuscript pages for AFFC and he wound up with 1527 by May. If he has half of ADWD left to write, he might not finish by May (see first update below).

Mind you, all this is conjecture. The only person who can truly measure the progress of A Dance with Dragons is George R. R. Martin himself. He promises to report such progress on the Official Website and cautions all of us not to believe any "news" about the next book unless it comes directly from him. This includes the publisher's website and retailers (like Amazon.com) who might guess at the release date or the book's page count.

To sum, all we can do is wait. We waited five years for A Feast for Crows and I don't believe we'll have to wait that long for A Dance with Dragons. We will monitor any updates from GRRM and report them here. Hopefully that will be enough to dissuade you from e-mailing GRRM about ADWD. For that matter, there's probably no reason to ask us either because, if you've read this article, you already know everything we do.

Updates

July 2006: Obviously, May passed without an update from GRRM. On June 30, GRRM wrote of ADWD on his blog, "I still hope to deliver it this fall, or by the end of the year at the latest." He did not detail his progress on the book.

December 2006: With the new year fast approaching, GRRM admitted on December 6, that ADWD would not be finished in 2006. He decided against giving further estimates on the book's completion, as missed deadlines have only added to his--and fans'--frustration.

January 19, 2007: Alongside the announcement of HBO's adaptation of A Song of Ice and Fire, Variety reported: GRRM "has nearly finished the fifth installment, but won't complete the seven-book cycle until 2011."

February 15, 2007: On his Official Website, GRRM reiterated that he will not provide ADWD progress reports: "The truth is, these updates do make me feel like a twelve-year old trying to explain to teacher why he isn't turning in his essay, and knowing she isn't going to buy the 'dog ate my homework' ruse any more than you guys do."

November 26, 2007: In an interview with Entertainment Weekly, GRRM insisted, "I'm working on it as hard as I can. Writing it tough sometimes, and it doesn't always go as fast as you want it to. [Sighs] One thing I've learned is to stop trying to predict when it's going to be done."

February 8, 2008: GRRM wrote on his Official Website, "If I can just finish DANCE this spring, there's even a chance the book itself might be on sale in Calgary." Calgary refers to the World Fantasy Convention, which takes place October 30-November 2.