Mobile WiMax promises to be fast, cheap and, if Sprint Nextel keeps its word, available nationwide by 2009. 3G service, while slower than mobile WiMax, is already widely available. Both technologies are designed to cover wide areas.
By contrast, public Wi-Fi hot spots require you to go to them. That begs the question: Can Wi-Fi hot spots in public places such as coffee shops and airports survive the onslaught of ubiquitous wireless access? And if they do survive, how will they change?
There is a wide divergence of opinion on this point.
"Once the price gets low enough for wireless broadband, why use a Wi-Fi hot spot?" asked Tole Hart, an analyst at Gartner.
"There's still a good future for hot spots," said Jack Gold, principal of J. Gold Associates. "For one thing, 98% of notebooks have Wi-Fi built in."
Hart did not predict that hot spots will go away, and Gold did not say that they will dominate mobile access in the future. Rather, while they, and other analysts and industry figures, may differ on the details, they do agree on two key points. First, hot spots will be different in the future than they are now. Second, how we access the Internet while mobile, and what we access, will soon start to change.
In the short term, public Wi-Fi hot spots will continue to be a common way to connect, the experts agree.
"3G is still expensive, and WiMax clearly will take some time," said Peter Jarich, an analyst at Current Analysis.
In particular, he noted, 3G (third-generation) access is priced higher than most consumers want to pay. Typically, operators charge $60 (£30) a month with a two-year contract, although lower-priced but more limited plans are available.