The G16 shows extremely subtle improvements over the G15 -- but you really have to scrutinize to see that there's slightly less detail degradation (I think the exposure difference is from slightly different angles during the tests, which were a year apart). The Sony Cyber-shot DSC-RX100, while not perfect, is still better, in part because the higher resolution provides better preservation of detail.
Canon pushes the saturation so that reds get a little too glowy, but that's pretty typical. Generally, the colors are pleasing. Disappointingly, though, you can't use the neutral color profile when shooting raw or raw+JPEG.