- cmake (from dmg)
- boost (wound up getting this from macports, too)
- flann (regular ann is already my best friend!)
- qhull (from macports)
- gcc 4.5 (from macports, website version is incomplete)
And this is how gcc gets update and actually used (thanks to help from one of the PCL mailing list members):
sudo port install gcc45
sudo port install gcc_select
Run gcc_select to identify versions available: "gcc_select -l"
Select gcc45, in my case is was: "sudo gcc_select mp-gcc45"
More helpful help: https://code.ros.org/lurker/message/20110401.025659.de4eecd0.en.html