I could be wrong but I thought the reason that the N810 Wimax died, was because everyehere else except the US already has a reasonable mobile network suitable for data transfer?
Then the iphone came and looks like the US will slowly work it's way towards 3G/GSM, and none of the other international carriers want to invest in a new technology when they can make do with the current roll outs and investments?

(I know there is one place in the UK with wimax, but the big roll out that was supposed to happen, just didn't)

In which case there is little point in having wimax?