From the passholder website!
New Fantasyland Passholder Preview
Be among the first to experience the enchantment of New Fantasyland during a special Passholder Preview in November 2012! Upon completion, Fantasyland will nearly double in size " for the largest expansion in the history of Magic Kingdom Park.
Registration details are coming soon and will be communicated via email and on the Passholder website. Event capacity is limited, so be sure to watch for these updates! Valid Magic Kingdom Theme Park admission is required to attend this event.