Hi, came across this software and have to say I was impressed. Simple but powerful and using zones, like the zone system to impove images. Macworld has a review, for more info. Also, look at the tutorial movies for how the software works; very simple and elegant.
There is a discount for users of Aperture/Lightroom and CS users until August 15, saving 50 dollars. They also have a demo. JonL
Review of Lightzone