Photograbber has a plugin system which is based on the BDCP2 API created by Graham Wharton (Creator of 'Exposure!'). With this system it is possible to add support to more cameras. If you have developed a BCDP2 compatible plugin for your camera (or just found one somewhere), just copy it into the 'plugins' folder and PhotoGrabber will detect and use it.
At this moment PhotoGrabber only supports PTP (Picture Transfer Protocol) cameras. In the future Mass Storage and Bluetooth support may be added.