Disney released a video showing the new circus themed Dumbo queue. You receive a restaurant style buzzer that tells you when it is your turn to ride. Then you wait in an air conditioned area with a circus themed playground of sorts. It looks very well themed and I am sure kids will love running through there.
From the Disney Parks Blog:
This innovative queue area will completely redefine what it means for guests to prepare for a Disney attraction. Here’s how it will work: Guests arrive at Dumbo’s big top and receive a circus ticket pager that virtually holds their place and notifies them when it’s their turn to board the attraction. Kids (and kids of all ages) can then become part of the show inside the tent by enjoying circus-themed play experiences, while Dumbo flies high above.