The 802.11s standard for mesh networking coalesced last week: Two leading groups with separate proposals, instead of slugging it out for a year or two, asked for and were given permission to attempt to merge into a joint proposal in January. At last week's IEEE meeting, the joint proposal was unanimously confirmed as the basis on which to proceed.
What this means is that within a year, there could be a unified standard that mesh devices could conform to for interoperability. I wrote in the Economist this week about one risk to municipal networks' early adoption was that at least four major metro-scale mesh equipment vendors are still categorized as startups. A shutdown or change in direction could leave superannuated equipment scattered like Metricom's or Vivato's.
A standard at least moves towards the potential of a trade group emerging that could set profiles--a la WiMax Forum--for kinds of mesh behavior. There could be single radio, switched multiple radio, contention-free sectorized mesh, and other profiles probably designed by frequency (2.4 GHz, 4.9 GHz, and 5 GHz); it's unlikely there would be a one-size-fits-all. Standards open industries to additional competition, but they can also soothe worried purchasers.