Atlanta is one of a handful of cities with 4G wireless service already available. This first salvo in the race to 4G is an implementation of WiMAX, which claims speeds comparable to Wi-Fi over much larger areas. I have been using 4G service for about two months now, and on the whole I'm impressed with it, but there are certainly some gotchas in comparison to using 3G cellular data service.
The WiMAX network was developed by Sprint and Clearwire with funding from industry heavy-hitters like Intel, Comcast, and Google. As such, there are several different vendors for WiMAX service, but they're all using the same network. I'm using Clearwire's CLEAR service, but as far as I know, there shouldn't be any performance difference between it and Sprint's 3G/4G service or Comcast's High-Speed 2Go.
So how does the service work? The short answer is that it works very well. It seems to work in all the areas advertised, and even gets good reception in large buildings. The falloff outside the working areas is very sharp though, so there's less of a chance to catch a weak signal as you could with a 3G card and hope to get marginal performance. There are marginal areas on the periphery of the coverage map, but they are very narrow zones. Go outside of them by even a quarter-mile and you'll probably find that you don't have any service at all.
As far as the performance goes, it easily beats 3G service in the same area. I use AT&T for 3G service, and my wife uses Verizon. Comparisons between their coverage areas aside, they seem to be what-and-what as far as speed goes when they both have 3G service. But CLEAR beats them both easily. Web pages and email messages download noticeably faster than on the 3G networks. That difference becomes more apparent when you're using multiple bandwidth-hogging applications at the same time. With a CLEAR Spot Wi-Fi adapter, multiple computers/devices can be on the same connection without a huge performance hit. And since the data use is unlimited, you don't have to be as timid about your use as you do with the 5 GB monthly cap on the 3G services.
Since CLEAR is advertised for use in the home, it's fair to ask how it compares to DSL or cable Internet service. In comparison to home Internet, however, CLEAR's service comes up short of cable or fast DSL. I would probably compare it to the middle tier of DSL speeds. Streaming hi-definition video isn't without some hiccups, but it's impressive to me that you can even do it over a wireless connection. With a 5 GB cap and slower performance, I certainly wouldn't try it over 3G.
When it comes to lowest cost, CLEAR is the winner hands down. CLEAR is cheaper than both Sprint and Comcast, but there's a catch. With CLEAR and Comcast, it is possible to get a cheaper 4G-only plan. That means that if you're outside the 4G zone, your device will not work at all, but a combination 3G+4G device will still work by switching to the slower 3G network. That additional 3G coverage is about $20 premium on top of the regular 4G-only prices, and it comes with the same 5 GB per month data limitation.
4G WiMAX is a service that I heartily recommend if most of your use will occur within a covered area. My biggest frustration with the service is that my home in southwest Atlanta is about three miles outside the coverage zone, which is all the more confusing given that there are small towns 20 miles from downtown Atlanta that are covered. Also, CLEAR's driver for Mac OS X is still in beta and only supports Leopard. That means that Mac users running Tiger or Snow Leopard are out of luck for now. Sprint and Comcast claim that their adapters are Mac and Linux compatible, but I cannot verify that. There seem to be no driver issues for anyone running Windows.
If most of your mobile Internet use is in within a covered service area, 4G WiMAX service is definitely worth the price. It will be interesting to see how the market shapes up as AT&T and Verizon (and maybe even T-Mobile) bring their 4G LTE services to market. Whether WiMAX can stay competitive against LTE remains to be seen. But as the only 4G game in town, WiMAX wireless Internet can't be beat.
It appears that CLEAR has released a Mac OS X driver that is compatible with both 10.5 Leopard and 10.6 Snow Leopard. I have installed the driver on my computer and it seems to work so far. I'll report back if there are any glitches, but this is good news for Mac users who have been holding out on CLEAR for lack of driver support.