Some updates on the OS X build front.
I've decided the way I was doing SDK builds wasn't entirely correct. I was building against the SDK of the oldest version of OS X we want to support (currently 10.5 or 10.6). That is easiest in some ways: it locks the API in, so you don't have to worry about weak linked symbols crashing at runtime if you don't check them, and you don't have to worry about lack of backward compatibility on some system libraries. The tradeoff is you are using an old API which may have less features or may not work correctly with new Macs. I think this is the case for Retina displays (unconfirmed), as the graphics APIs are being limited to 10.6 features.
To remedy that, I have been adding proper, runtime weak symbol checking whenever there are API differences between OS X versions we care about (typically 10.5 -> 10.6, or 10.6 -> 10.7). The code becomes a bit yuckier, because you have to do compile time checking (to avoid compiler errors) and run time checking (to avoid loader failure or crashes). I have also stopped using the Apple-provided zlib, curl and libxml2, and added those to the OS X library build script. Now I have a patch that makes it possible to build with 10.5 support in the 10.8 SDK and beyond, for both 32-bit and 64-bit builds.
This means the bundle build process is easier on my end, I only need a single Mac and if it's 10.8 or newer, we benefit from the latest APIs but keep support for the oldest OS X versions we want (hopefully with little or no additional work). This also means it's possible to have a universal app bundle, with both 32-bit and 64-bit binaries combined, so it should run well on *any* Mac with OS X 10.5 - 10.8.
So here is a universal test bundle I made based on SVN r13920, what I would really like is some users with Retina displays to give it a try and see if it improves the game in fullscreen mode. But anyone with OS X could test if it runs normally:
https://docs.google.com/file/d/0B-qlXhiirMW3ZVh4ZkNHNEFjVkU/edit?usp=sharing
One known regression is Atlas won't work on 10.5 due to some STL template issues that I fixed in the engine but not in wxWidgets (dyld will say it failed to load due to a missing symbol).