Well, it's only partially 5. Wavelength has three possible values, polarisation has two, and Z has ten. I would describe it more like encoding six channels per layer... but that's just me, maybe they'll get more layers/colours/polarities.

I think the article misrepresents the result.

Isn't this exactly what Google's location api does? Only without the cell tower and GPS functionality?

http://code.google.com/p/gears/wiki/GeolocationAPI?redir=1

I would imagine it would be hard to compete by wardriving when Google has an army of mobile phones querying where they are reinforcing the database.