Ever since Sony released the NEX series of cameras, I have been considering to buy one of these babies. However, their relatively large size related to the HX9V compact has stopped me. Basically, these cameras do not fit in your pocket, which means for me that I will not take it on every journey and not have it with at that unexpected moment. Then Sony surprised me again with their RX-100 camera. A truly amazing piece of hardware, packing a massive 1 inch sensor with a light-strong Carl Zeiss lens in a compact package. At 35.9mm thick, it less than 2 mm bulkier than the 34mm of the HX9V, which stilll fits any pocket (although it is slightly stressing your jeans pockets). At 1 inch (13.2 x 8.8mm), the RX-100 sensor is more than 4 times larger in surface than the 1/2.3" (6.17 x 4.55 mm) sensor of the HX9V. Obviously, this results in a much higher light sensitivity, larger dynamic range and better contrast. However, the image stabilization performs less than its smaller brother and the zoom range is strictly limited (the 3.5 times zoom from 28-100mm vs. the 24–384 mm, 16x).
Watch a very nice comparison between the HX9V, the RX100 and the NEX-5 camera: