From the Disney Parks Blog

Earlier this month, our friends at Walt Disney Imagineering celebrated a milestone in the New Fantasyland expansion with the laying of the first piece of track in the Seven Dwarfs Mine Train attraction.
The First Track for Seven Dwarfs Mine Train is Laid at Magic Kingdom Park

The attraction, which is set to open in the park in 2014, will take Magic Kingdom Park guests on a musical ride into the mine “where a million diamonds shine.” The coaster will feature an innovative ride system with a train of vehicles that swing and respond to every twist and turn of the track. The journey will be accompanied by music from the classic Disney film and animated figures of Snow White and the Dwarfs.