I recently installed pkgsrc for osx, and so far so good. (I've never liked the idea of installing software by compiling it.)
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.
Hmm I didn't know that Joyent maintained their own packages for non-SmartOS platforms. The OS X packages seem to be limited to 32-bit versions and even though you didn't mention this I noticed their Linux packages seem to lag behind pkgsrc upstream. What is the advantage of using their packages over the OS X and Linux ones offered by NetBSD? https://www.pkgsrc.org/#platforms
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.
(pkgsrc is the NetBSD version of FreeBSD ports, but its always been portable to other systems).