Do we sort of pretend WiMax is 4G or not?
I've recently been testing the Sprint variant.
If you're in a good signal area, then this isn't 3G; it's far superior.
However, it attenuates a lot. I can't think of it as dependable, unless I'm stationary in a good area. I can drive for 20 seconds and lose a full set of bars
(signal loss, not fluctuation).
I've also noticed, that Sprint's coverage maps reflect what looks like a bizarre deployment strategy.

Hudson FL
The darkest blue areas are indoor coverage; the next-lighter blue is outdoor only.
This map shows small pockets of coverage, some of them in isolated areas.
It shows one large swath of 4G stretching into the Gulf; most of it offshore from a decommissioned strip mine.
Not knowing how they construct these maps, I don't know what might be error, an anomaly, potential/future coverage or actual coverage.
Could some of the small areas be targeted coverage?
They could be backhauling from one of the available ISP's.
Maybe the map includes WiMax Femtocells!
Anyway, when time allows; I'll visit a few locations and see if there is anything to see.
NV