You can already have that with pkgsrc for osx - joyent maintains the osx binary packages see http://pkgsrc.joyent.com/
(pkgsrc is the NetBSD version of FreeBSD ports, but its always been portable to other systems).
(pkgsrc is the NetBSD version of FreeBSD ports, but its always been portable to other systems).
However this project could really use some nice webpages and instructions to promote it. It seems like most Mac devs have never heard of it. And much of the info is pretty minimal and seems like it assumes you understand NetBSD packaging.
I have generally used source not packages for non NetBSD platforms, other than when I tried out SmartOS and it is all set up. If you have a chunk of disk space, a fast computer and some time you can compile them yourself, and if someone wants to support osx 64 bit that would be great.