John Taylor is the primary spokesman for Sprint, and he lays out the reasoning for the $10 fee on his Blog (
More Detail on the Sprint EVO 4G $10/Month Premium Data Charge)
Here's
4G Coverage and Speeds where you can check Sprint's 4G coverage. Select a state in the drop-down, and then in the City drop-down all the cities within that state will show up. Select a city and it will take you to the 4G coverage map for that area.
Sorry, I couldn't resist the Laredo crack.
What's happening now with Sprint's WiMax 4G technology is similar to what Verizon went through when they first rolled out EVDO (3G). Because the data requires different towers than voice data, new towers have to be installed, and it's the same with 3G and 4G towers. When EVDO first came out, it was only available in a few larger cities, and then spread outward from there. Now I can get 3G in some of the most bizarre places. Sprint will eventually get there, too. On the other hand, Sprint's WiMax (from Clearwire) is, for lack of a better phrase, a quick and dirty way to get 4G out there. Sprint plays it up like they've beat everyone to the punch, and they'd better play it up like that if they want to sell some phones, but Verizon will be rolling out LTE in 25-30 markets this year, and by 2013 the Verizon 4G coverage map will look like today's 3G coverage map.
Of course, that also means that Sprint's WiMax will have a 1-2 year head start on availability and usability. But Sprint won't be able to roll out massive coverage as quickly as Verizon, specially when you consider AT&T is also going to use LTE (as will nearly every other GMS carrier around the world), and Verizon and AT&T's towers will share each other's users. So with Verizon and AT&T teaming up installing towers, Sprint has to hit it hard and heavy from the get-go. Sprint can, at a later date, migrate or even piggy-back LTE on their WiMax network, but it's gonna cost them to do it.
There isn't really any "WiMax versus LTE" war going on, since they can be used together. LTE is actually better suited for front line access, and WiMax for the backhaul end of things (WiMax is used extensively in digital television surveillance, so it excels at efficiently transporting large amounts of data). For people who don't travel outside their immediate area very often, it'll simply come down to which one is available, since some people will have access to one or the other, some will have both. But travelers are going to eventually want to go with an LTE network, most likely.
The biggest upside to LTE and both Verizon and AT&T going with it, is that most phones will work on either network, so the carriers will have to actually employ things like excellent service to lure and keep customers, rather than exclusive phones. That's where Sprint may get burned in the long run, unless they migrate to LTE, as well. So far, neither Verizon nor AT&T have expressed any desire to make it easy for Sprint to join the LTE crowd, so Sprint is left with trying to get as many people quickly hooked on WiMax as they can, and then hope they don't jump ship later on. Since the differences between WiMax and LTE are really insignificant when you come right down to it, there won't be an reasons for people to jump ship for speed or other performance issues when LTE becomes available in their area. That's what Sprint is banking on.