It's been a couple of years, but I remember the main pain points being:
* versioning: we wanted to get very specific versions of things (DB servers, JDK, etc.) on our dev boxen to replicate production as closely as possible
* breaking changes to OSX: it seemed as though every new version of OSX broke All The Things. It wasn't easy to do what we'd do for Linux, that is, mandate "start from a fresh installation of Ubuntu 12.04 LTS"
* breaking changes to tools: the software management tool we were using (I forget the name, it was written primarily by a guy here in Melbourne) kept changing in ways that made things difficult
* massive installations: I seem to recall downloading GiB of data per machine, something about installing XCode through iTunes
* iTunes: again this is going from memory, but I recall there were certain tools we used that wouldn't install nicely from the CLI, only through iTunes
* hardware-specific OSX discs: I also recall having issues with having to have the right installation media for the right hardware (ours was, errr, not homogeneous)
All in all, it was death by a thousand cuts. Everything 'sort of' worked, but new versions changed things, new hardware changed things, ... it was very, very rare to receive a new Mac and just be able to deploy our dev environment to it.
Perhaps things have changed for the better in the past few years, and we certainly did have an odd (publishing industry specific) set of tools and requirements.
But the experience really did suck.