I work with SkyPilot Networks (www.skypilot.com) hardware and have a wireless mesh network set up with 30+ nodes that I am managing. I was getting 5.8Mbps of throughput even when I was a couple of hops away from the gateway according to iperf! That's not bad at all! I think that all of this WiMAX stuff is very exciting, and I even wrote a short paper concerning future development which can be found at http://www.duke.edu/~jyw2/spectrum.html