Few days ago I found AirGrab WiFi Radar
(have you heard about this tool?), it's a program to display information about Apple Airport base stations and other WiFi (802.11b/g/n) wireless access points. Using this tool you can determine most popular WiFi channels and select optimal channel for your WiFi network.
I think it 'll be helphul to all... (btw, it's free....)
you can read more information on the site...