Whether this makes any difference to the software and how useful it might be in some of my work, is an entirely different matter...
There is certainly some merit in being able to change brightness without butchering color (to use colloquial terminology
). Tonemapping needs to do a lot of that, to trick our 'eyes' into believing that what we see resembles the original scene.
I've been following the progress in Unified Color's software implementations, but it didn't convince me enough to part from some of my money, yet. With the recent developments in ACR/LR process version 2012, it will be even more difficult to make a difference, especially since things like generating the HDR data from exposure brackets seems to have improved in Photoshop as well. But that's a different subject.