All three space shuttles, Atlantis, Discovery, and Endeavour, are currently at the Kennedy Space Center in Florida undergoing processing to prepare them for public display. Since there are only two active processing facilities, NASA had to do a shuttle swap, resulting in a unique photo opportunity between Endeavour and Discovery.
While Endeavor was being cleaned up inside Orbiter Processing Facility-1, Discovery was parked inside the Vehicle Assembly Building. Now it's Discovery's turn to get detailed, so NASA had the two spaceships switch places, as KSC spokesman Allard Beutel explains:
"Endeavour and Discovery switched locations -- a shuttle shuffle. It's just a storage thing, is what it comes down to -- we have three shuttles and two locations. We've never had two shuttles pass each other to go to two separate locations, this was the first time we've ever done this."
Atlantis is also still at KSC, undergoing preparation in the Orbiter Processing Facility-2. I'm keeping my fingers crossed that NASA will see fit to line up all three shuttles for a sweet photo op before they get shipped off to their final destinations: Discovery to the Smithsonian, Endeavour to the California Science Center, and Atlantis just down the street to the visitor's center at KSC.