From www.wdwinfo.com

Disney releases CGI video of new Seven Dwarfs Mine Train attraction
Apr 8, 2014

Excitement for the Seven Dwarfs Mine Train at Walt Disney World's Magic Kingdom continues to build as it gets closer to opening. An exact date for the debut hasn't been announced, but a "preview event" will be held for members of the media on April 30-May 2. Because the invitation doesn't specify that it's a "grand opening," the attraction may not open to the general public at that time, but it's safe to assume that it will be soon.

Yellow Shoes Creative Group, who is currently developing advertising for the attraction, has released a new CGI video that gives a glimpse into what the ride will be like.