Basically, these days I recommend cmake as the sane build system that runs everywhere. I don't know about PCs running MacOS, but it works just fine under Linux or Windows and you can do whatever magic you want; it makes simple things easy and complex ones possible.
I wouldn't recommend CMake without qualifications.
It is vastly inferior from the perspective of the end user. Any autotools package can be handled with "./configure && make && sudo make install", and you can change it up by "./configure --without-gtk --enable-network --prefix=/opt/crazy CFLAGS='-O0'" and then make a package with "make install DESTDIR=/tmp/package". Try doing that in CMake, you'll see what I mean.
The syntax is also really terrible, in particular, If/Else. The documentation is not so good, in particular, it's available online as one big block of text and they want to sell you a book.
Finally, CMake doesn't solve the one problem I was complaining the most about, which was the ability to set per-file compilation flags. This is not an optional feature in my eyes -- it's necessary for avoiding cross-contamination of -D_GNU_SOURCE turds picked up by pkg-config, and it's necessary for writing libraries that use processor features that might not be available at runtime, like SSE3.
I think CMake, like Autotools, has a niche in which it does best. "Simple things easy and complex things possible" is a nice motto, but the truth is really boring -- CMake and Autotools make different things easy and different things possible. CMake's niche is medium-large projects with medium amounts of complexity. Projects that are complex, like Firefox or FFMpeg, tend use Autoconf with custom build systems.
