Hi, a friend told me the WDW resorts were opened for booking in 2012. Early! So I looked at Aulani. There were some dates that I would get an message saying there were no rooms available - Thanksgiving/Christmas. So I'm not sure if some holidays are truly already sold out, or if 2012 has some blocks/time frames not opened for booking yet.
So, depending on what part of 2012 you wanted to go - you may be good to go. We wanted Christmas 2012, but are opting to do something else and push this back to 2013.
Good luck!