It remains to be seen if the buzz gets anywhere near the hoopla surrounding the iPhone's initial launch last June, but a line has already started forming outside Apple's Fifth Avenue store in New York. The iPhone 3G goes on sale at 8 a.m. local time on Friday. Outside the U.S., launch times and dates vary, with the earliest also being July 11.

A World Phone

The newest version of the "phone that changed the world" comes not only with faster 3G connectivity , but a lower price -- $199 for the 8GB model. It is also now in sync with the most prevalent telecommunications networks in countries around the world, and will be available in more than 70 countries.

Avi Greengart, an analyst with industry research firm Current Analysis, said the addition of 3G, plus a "dramatic increase" in the number of countries where the iPhone is available, should result in the device selling "considerably greater" numbers outside the U.S. than in the past.

For the U.S. market, he added, the price drop puts the iPhone 3G more in the range of some smartphones.

Greengart noted two differences between this week's launch of the iPhone 3G and last June's launch of the original iPhone.

A big one, he said, is that this time the iPhone has corporate e-mail support. "This opens up the iPhone as a choice for those customers who are interested in a smartphone for its e-mail capability," he said.

Among the criticisms of the original iPhone at launch was its lack of support for enterprise use, and there have been reports of increasing demand among employees to use the device.

'Mobile Computing Platform'

The second big difference, Greengart said, is that the iPhone 3G is "becoming a true smartphone," since it has been opened up to outside, third-party developers . Users will be able to obtain third-party applications from either Apple's iTunes Store or its AppStore.

Greengart said the availability of outside applications means the iPhone is now clearly "a mobile computing platform." Other smartphones also offer that potential, he said, but finding and using their applications has often involved wading through a fragmented marketplace. With applications centralized in iTunes and AppStore, he noted, Apple can offer a unified marketplace.

There is also a third difference this time around. Instead of taking an iPhone home to be activated over the Net, customers will be required to activate the phone right in the store.

The original at-home method allowed Apple to sell more phones faster, but also led to complaints. In addition, in-store activation will allow AT&T to reduce the number of customers who buy the device to unlock it and resell it in other countries.