As I've recently acquired the latest and greatest Sony Xperia Z as an upgrade from the Xperia S, I thought to share few comparison camera shots between both handsets. Not being an imaging expert my feeling is that the Z generally produces better quality pictures, however I have noticed on few occasions that it does fairly heavy post-processing and fine details are sometimes blurred a little. Yet still, the noise seems to be much reduced in the Xperia Z shooter, which was major concern with Xperia S camera.
Few sample shots below - just click on each for high-res version. All photos were taken using fully automatic mode on both devices.