Mike Donges of MumboJumbo has made a few comments about upcoming patches for the Mac and PC:

The Mac release will have integrated many of the issues that will be fixed in the PC patch. Because many of the issues on the PC are PC specific, those won't really be reflected in the Mac version.

Just to clarify, the first PC patch may not be version 1.1. We will probably version the full point releases only if they require cross platform network compatibility. For example, the PC patch and the Mac GM may both be 1.05. Or, the Mac GM may be 1.06 and the PC patch may be 1.05. Only when we need to release a patch that involves network compatibility will it get revisioned 1.1.

The origins of these quotes aren't known, but surely they are accurate since they come from Myth Village.