I used macports through two or three upgrades before switching to home-brew last year. Switching was one of the best decisions I ever made. In terms of MacOS package managers -- in the grand scheme of things it's not really a big deal. First world problems, right?

MacPorts is very, umm, opinionated. And doesn't seem to trust anything outside of itself. And has some weird opinions, too.

Example: For some reason, svn is a dependency for nmap. Forgot those gravity waves, the next nobel prize belongs to whoever can figure out why a network scanner depends on an obsolete version control system. So macports installs a shiny new version of svn. Which doesn't play nice with the svn that Xcode uses. Overtime I run (macport) svn from the command line it tells me to upgrade my repository, which breaks the Xcode svn.