There was a video of Batman getting out of the Batwing, talking to Gordon, hooking the device from the back of the HEMTT, talking and hugging Selina and then getting back in the Batwing. The Batwing rumbled and made helicopter sounds then 'cut'.
We had lots of paparazzi shots of the other end of the HEMTT vehicle. Selina pulls up on the batcycle. A woman dressed like Miranda was slumped in the front seat. Selina goes to the door. 'cut'.
There's no guarantee that he flies off with the device, but it's a safe bet considering there is photography of the device on the street with the Batwing flying (on wires, that will be digitally removed) above it.
After the fight between cops and militia outside City Hall the cop-extras were directed to look up at the roof of a building and cheer. This scene could occur anywhere in the movie, but it could well be the scene when Batman takes off and breeches over the buildings.
At the time I personally thought this reaction was going to be Bane throwing Batman's body down into the street.
