Here's a gallery of stunning aerial night-photos of London from Jason Hawkes, who notes, "I often shoot tethered to my MacBook Pro to check the sharpness of the images whilst I shoot." He's taking questions on technique at Boston.com, too.
Just before I first moved to London, some well-meaning friends took me up on Primrose Hill at night to "see the London skyline." I didn't want to disappoint them, so I oohed and aahed, but to be frank, the skyline, as seen from the hills, isn't much of an advertisement for the city, in which the majority of buildings are old, squarish low-rises. But London from the sky — that's something else entirely. Seen from that angle, London's purely magic. I'm convinced that the back-breaking queues for the Peter Pan ride at Disneyland are entirely driven by that opening trompe l'oieul flyover of London in miniature.