This turned into more of a rant, but input is welcome.
There doesn't seem to be a FOSS (or even low cost) wifi analysis tool. Ekahau, Chanalyzer, Acrylic, etc. are all $$$$$$. What's a guy trying to get relevant certs to do?
Wireshark will only show you actual wifi packets if you have the precise combination of wifi adapter, OS, and driver, and packet capturing is just one component. Spectrum analysis and evaluating mobility are also important. Seems like you have to already work in the industry to have access to these tools, and nobody's going to hire you without relevant certs which require knowledge of these tools.
(update: Someone's bound to mention Kismet. I only have a windows laptop, and kismet doesn't work [well] under windows. I do have access to a linux desktop, but wifi analysis on an immovable desktop isn't terribly useful.)