CMake is also very difficult to debug (e.g. to find out why a library test is failing), harder to fix once you've debugged it, has strange ways of accepting extra compiler/linker flags from the environment, has poor --help, tries to allow creating Xcode projects but mostly produces nonsense, etc...
I think it might actually be worse than autoconf in every way, which is surprising considering how bad autoconf is. The handwritten non-macro-expanding not-much-autogenerating configure/makefile in ffmpeg/libav/x264/vp8 is easier to deal with than either.
I disagree with you that autoconf is bad. Its design came from a lot of locally-optimal choices that don't look so good in 2011, and there's a lot of legacy code being copied around in people's configure.ac files.
To me, it's not perfect, but it's pretty good. Then again, I'm known to my friends as "that guy who knows automake" :-).
I think it might actually be worse than autoconf in every way, which is surprising considering how bad autoconf is. The handwritten non-macro-expanding not-much-autogenerating configure/makefile in ffmpeg/libav/x264/vp8 is easier to deal with than either.