Yeah, you're reading that right.
A Dance with Dragons will be published worldwide on 12 July 2011, by Bantam in the United States and by Voyager in the UK. That's about four months from now.
As a bonus, GRRM also unveiled the new American cover for ADWD, to fit in with the new editions of the rest of the series being published later this month. Interestingly, ADWD has variant covers, the gold one above and a silver one (otherwise the same) you can see through the above link.
Martin has also confirmed that A Dance with Dragons is huge, and may exceed A Storm of Swords in size. The hardcover will be over 900 pages in length, and once again the UK mass-market paperback will be in two volumes (the hardcover will still be in one). ASoS was over 420,000 words in length, which means that ADWD is so huge it notably outstrips even recent books like The Way of Kings, The Wise Man's Fear and Steven Erikson's last few books in size.
Good news, obviously!
Interview with GRRM about it here.
And since some have asked for a reposting, here are all the new American ASoIaF covers, which should be hitting the shelves across the USA by the end of the month: