see also:

• mirrorless camera systems
• Micro Four Thirds system
• Sony NEX E-mount camera system

• Ricoh offers an interesting design alternative with its GXR system in which each lens has its own sensor permanently attached to it and designed to match the expected usage of that lens.
• this may suit a few people wanting some mirrorless capabilities and the option of a point and shoot compact 10x zoom in the one system but its main downside is that as sensor technology becomes out of date, you not only have to change the sensor but the lens system as well, which is likely to mean a more expensive longer term cost.
• the body has a built-in pop-up flash, hotshoe and capability of adding an external viewfinder onto the hotshoe.
• the terminology on lens focal lengths belows are not actual but 35mm full frame equivalents.
• I really can't see this system going anywhere, particularly with the lack of progress in updating sensors or lens options

• back-illuminated 120fps 10.6 mp, 1/2.3“ CMOS sensor
• image stabilised 10x zoom
• 720p 30fps video
• ie. similar to many older 10x zoom point and shoot cameras

• 12mp APS-C 3fps sensor
• ie. similar to an entry level, older Canon or Nikon cropped sensor camera with a 32mm macro lens

• 1.6fps 10mp point and shoot size 4.7x crop sensor with VGA movies

• 12mp APS-C sensor
• 18mm lens giving 28mm in 35mm terms
• a more preferable option would be a Micro Four Thirds camera with the lovely Olympus mZD 12mm f/2.0 lens

• 12.3mp APS-C sensor
• you may as well just buy a Sony NEX E-mount camera system or Micro Four Thirds system with Leica-M mount adapter and get many more features and versatility