I think sony have put some good optics on there Z1,Z2,Z3...its quality is quit good
Nokia Lumia also have similar sized sensor .I am also waiting for WP10
I don't know. Optics play one part, software another.
After taking nearly thousands of pictures from Z1 compact, I can safely say that it has excellent low light capabilities, but in normal light, it is just like any other average cell camera. Honestly, the post processing is terrible, there is no option for raw capture and manual mode is....well, I don't think ISO/Exposure/WB only options count as Manual.
Lumias are way ahead in imaging....from the core app to better post processing and raw capture. Honestly I would have bought Lumia 930 if it was released a little earlier.
[MENTION=8593]izzikio_rage[/MENTION] , the lack of updates is troubling. In truest sense, Sony is trying to position their ILCs as DSLR replacements. Now, even entry level DSLRs from Canon and Nikon get regular software updates, even after two to three years of release. This neglect of mid-entry level line can cost Sony a lot, given both Samsung and Olympus/Panasonic push updates more often.