Out Of My Vulcan Mind wrote:
According to HBO's Facebook fan page
for the series, it's the first in a series of posters designed by fans.
Winter Is Coming believes the term "fan posters" means they're extra posters HBO has designed and released online for the fans, in addition to the main posters that will be used to market the series, rather than posters designed by fans.
Ah, got ya. Didn't consider that interpretation of the phrase.