HBO has updated their Viewers' Guide website with a lot of new information. Most notably, they added a new zoomable world map here.
Adam Whitehead, who has become an authority on all map-related matters, had this to say about the new map:
So is this map 'canon' for the books as well? Mostly, certainly as far east as the Red Waste and Lhazar. However, George R.R. Martin recently re-conceptualised the map of Essos past that region. The HBO map is based on older material and should not be considered canon for the books (although the approximate locations of Vaes Dothrak and Qarth should be correct, the coastlines and some of the geographic detail has changed).
Amusingly, since it doesn't show the known coast of Sothoryos, the map fails to resolve the age-old question of whether the Jade Sea is a landlocked semi-inland sea (like the Black Sea) or not. Speculation may continue, at least until The Lands of Ice and Fire map book (which will be canon for the books) is released in October.