I use and love it, but I sincerely wish they'd change the name and the UI. I'm a programmer, but even I didn't realize how much they were hiding in context menus at first until I had to search online to find documentation on how to do the few simple things I can do.
The multi-window thing I really don't have much of a problem with, though, even if it was hard to get used to at first. I don't have much use for the higher bit depths and such, but I can see his point about quality and why others need it.
The multi-window thing would be fine, but why does each window need a button on my taskbar? On both Windows or Linux, doing any serious work in GIMP destroys my taskbar's usefulness.
Then, which windows are on top of other windows is never what I expect, even after years of using GIMP.
In my opinion a multi-window image program is the way to go, but GIMP's implementation of it is not.
(P.S. I think Apple's Interface Builder's multi-window implementation is much much worse, however.)
The multi-window thing I really don't have much of a problem with, though, even if it was hard to get used to at first. I don't have much use for the higher bit depths and such, but I can see his point about quality and why others need it.
Incidentally, a lot of programs have problems with gamma. I think this link has been on HN a few times: http://www.4p8.com/eric.brasseur/gamma.html