The mesh uses the Optimized Link State Routing protocol to relay messages across the network.
OLSR Mac OSX binaries are available here. However installing and configuring OLSR for Mac requires a lot of under-the-hood work with the Apple Unix layer.
If anyone has the skill and is able to help establish a stable config for OLSR on Apple, we shall certainly assist where we can. However we do not have the human resources to deploy Mac OLSR mesh-wide.
In addition, we envisage deployment of newer, better neighbour-to-neighbour routing protocols in the near future. Therefore we suggest that Mac users buy a Linksys router and cable into it.