It was closed all year until November 21, 2008, when they opened it up for the Small World Holiday overlay they do every year - where they decorate it for Christmas and mix the track with Jingle Bells throughout and Deck the Halls (in the finale/white room) They then shut it back down on January 4 to complete the character installation. They moved the Rainforest scene before they opened it for Christmas.
It reopens permanently this Friday, 2/6.
PS -

my bad - a bunch of us addicts loved your AC bar so much we kind of borrowed it. If you say no, we'll stop using it, but it was such a genius idea..... Well - dang Pete!