Digital Photography School has a nice gallery of kite aerial photography (or KAP, as it’s called amongst insiders):
I have to date built various kites myself and actually also one of the KAP rigs shown in the gallery and have done some KAP experiments myself. KAP is lightweight, can produce affordable aerial photography and is thus an interesting acquisition method for spatial data. For these reasons it is sometimes used for archaeologic studies and exploration, see for example here or here.
Despite ever more popular quadro- and other copters and their advantages (for example, no need for wind), I think KAP may keep a niche, for example in applications where noise may be an issue or where an especially heavy payload needs to be lifted.
Impressive! I’d love to try out KAP, but we’re into BAP (i.e. Balloon Aerial Photography), see here: http://geosocialite.wordpress.com/2012/08/17/my-big-blue-balloon/ It’s the alternative when there is no wind and you don’t want or can’t use a x-copter (noise, legal restrictions, budget).