so since 6 weeks I'm now working at Kitware, Clifton Park, NY, USA.
So what can I say about CMake (since this is of interest for KDE) ?
It was definitely a good decision to switch to CMake. It is maintained and developed by a team of highly skilled software engineers, mainly Bill and Brad. It's maintained carefully and new features are designed with flexibility, backward compatibility and "usabilty" (if you can say so for a build system) in mind. CMake comes with a big suite of unit tests, consisting of over 80 separate tests, each one testing several features of CMake, which gives several hundred tested features with each full test run. These tests run nightly on a big variety of platforms, and on some platforms continuous builds are running. Without this continuous testing it would be impossible to ensure the quality of CMake. We should have this too, at least for kdelibs on let's say Linux, FreeBSD, OSX and Windows.
I'm currently setting up a Nightly build of kdelibs (from alpha1) with CMake from cvs head. While this doesn't test kdelibs, it ensures that there go no changes into CMake which might break the compilation of KDE. Which is good both for KDE and for CMake.
What new stuff will we get in CMake ?
CMake is used at Kitware for all their software products, so there is time, man power and also some money behind CMake development, which ensures that CMake will be there and well maintained for the next years. It also means that CMake will get support for all the new stuff as it comes out, like 64 bit systems (ok, not so new anymore), OSX on Intel, universal binaries, Vista (yes, now that KDE4 is portable to Windows that's also interesting for us) etc. Otherwise Kitwares customers wouldn't be happy...
So, ignoring all the features of CMake itself, just the development behind it makes it a very good choice for KDE :-) ...and of course also for other projects.