More noticeable is the slight change in positioning of the speakers and microphone in the new design. Although I haven't yet noticed a big difference in calls made while holding the phone to my ear, ringtones or application sound effects are definitely louder and clearer when played through the external speaker. Even more dramatic is the improvement to the speakerphone, which is now among the best such feature I've heard on a mobile phone.

New features specific to iPhone 3G

Most of the "new" features in the iPhone 3G are really part of the iPhone 2.0 firmware update that can be installed on any iPhone, new or old. There are, however, two big differences between an original iPhone and an iPhone 3G. The first is, of course, the 3G network access implied in the new iPhone's name. This is, in fact the most significant difference between the first iPhone and the new model—and it's the most significant reason to upgrade.

It sounds cliche to say there's no comparison between the data capabilities of the two phones, but sometimes cliches are true. This is one of those times. The informal testing I've done so far has involved turning Wi-Fi access on and off—both at home and at a handful of Wi-Fi hotspots in my neighborhood. While I won't say that AT&T's 3G service matches my high-speed cable modem connection, it does keep pace with the mom-and-pop coffee shop down the block (which I relies on an entry-level DSL connection and which was being used by a handful of laptop users).

Certainly, the performance was significantly faster than the EDGE network-based iPhone. Loading a variety of Web sites and even browsing YouTube can be done in a reasonable amount of time, whereas using EDGE meant pages loaded at a painful crawl. Even checking e-mail over EDGE seemed agonizingly slow. Truly, given the Internet features of the iPhone, this is the performance the first model should have had and. For me, the faster download speeds are well worth the price of upgrading as well as the extra $10 a month for 3G data service that is required in the iPhone 3G plans.

The second major addition is built-in GPS. Although the original iPhone can approximate your location by triangulating between available cell phone towers and known Wi-Fi hot spots, its effectiveness varies widely depending on where you are; It could be within 10 or 20 feet in one spot and off by a mile or two off just a short drive away. The iPhone 3G's GPS could pinpoint my location to within less than five feet in almost any location I tried. And despite some concerns from veteran GPS users that the iPhone might take a long time to acquire GPS signals and calculate a position, I found it could do so within a minute on each try.