George R.R. Martin confirms it in his own words (on his blog) that the new release date of July 12, 2011 for A Dance With Dragons is real. It's not some publisher's mistake or hopeful assertion, not that we've seen one in the past. It's the real deal! ...and it's HUGE!
((For what it's worth, the book's a monster. Think A STORM OF SWORDS))Above is the newest cover, as shown on his blog. The Wertzone has another version that'll be coming out as well. And here's a timely interview on EW.