Hahaha. The speed limit of current-generation fibre is thousands of times anything that's even on the horizon for wifi. The reason for that is simple: the maximum data transfer rate is defined by wavelength - and while the wavelengths in the wi-fi spectrum are in the vicinity of a tenth of a metre, the infrared wavelengths used in fibre are a few millionths of a metre. A single hair-fine fibre can carry many terabits (millions of megabits) per second - or approximately all of the 3G, 4G or whatever-G mobile data in an Australian capital city. A single fibre. And unlike with wifi, when you fill up that one you just light up the one beside it (running less than a millimetre away in the same bundle). With wifi, once you're saturated that's it. And before you start, all the fancy multiplexing options being used to squeeze every last bit of capacity out of the microwave spectrum is just as applicable (and then some) to the infrared spectrum.
