Intel's newer low-power Atom netbook chips -- and the coming "Pine Trail" upgrade -- should make it easier for vendors of the smaller mobile computers to include more connectivity options. I'd think that Apple would want the trifecta of WiFi, 3G, and WiMax to ensure maximum compatibility options.
Of course, for many vendors, the pricing of these units is so tight that multiple radios becomes a costly option. I would expect, however, that Apple could charge a premimium for an iNet over its $500 competition.
Clearwire LLC (Nasdaq: CLWR) already has connection manager software for Macs on its books, although I imagine that Apple would want any WiMax offering to support enough frequency bands to make its product viable as a global sell.
— Dan Jones, Site Editor, Unstrung