Recently it seem a lot of projects are switching to CMake.
Do you know OpenWengo ?
Or take the premier Open Source Desktop Publishing application, Scribus . They switched already to CMake, and apparently without major problems: http://public.kitware.com/pipermail/cmake/2006-April/008847.html
All apps listed above are Qt4/KDE4 applications (except obviously cdrtools), but there are also other projects switching:
Do you know Chicken Scheme ? CHICKEN is a compiler for the Scheme programming language, available under the BSD license. Chicken scheme can now also be built with CMake: http://galinha.ucpel.tche.br/chicken/INSTALL-CMake.txt .
CMake also seems to be popular among researchers: both MOOS, the "Cross platform software for mobile robotics research", as also Orca, which is an an open-source framework for developing component-based robotic systems, are using CMake for building their software.
So, are we seeing the beginnings of a big change (at least for developers) ?
On the KDE side, there's one important thing to mention:
I also plan to improve the automoc implementation. Currently approx. 20 to 25 percent of the time of a cmake run are spent in automoc. I plan to move this from cmake time to build time and do it only if required. This will cut off quite some time.
P.S. and, well, if you really want to, you can even abuse CMake to convert wavs to mp3s: