With the iPhone 3G's release just days away, it's time to revisit the pressing questions relating to Apple's next-generation phone. We still don't know everything about this forthcoming iPhone 3G--and probably won't until we've picked one up on Friday morning--we do know more than we did immediately after Steve Jobs previewed the iPhone 3G at last month's Worldwide Developers Conference.

Since that time, AT&T has confirmed information about the iPhone service plans, while Apple has offered a guided tour of the iPhone 3G. Combined with more information we've gleaned from here and there, we're ready to take a fresh look at what you can expect when the new iPhone arrives on July 11.

What does the "3G" in the name mean?

If you're familiar with iPod naming conventions, the term 3G might make you believe that Apple is releasing its third generation of iPhone. No, you didn't sleep through an iPhone product introduction--3G in this case stands for third-generation mobile technology. It's a wide-area wireless technology that allows for much faster data transmission than the EDGE network used by AT&T with the iPhone right now.

How much faster is it than the current iPhone?

AT&T says that the iPhone 3G will have typical download speeds as high as 1.4Mbps versus average data speeds between 75Kbps and 135Kbps on its EDGE network. During Steve Jobs's keynote, it took 21 seconds to load a graphics-heavy Web page using 3G versus 59 seconds on EDGE. Similarly, an e-mail attachment took 5 seconds over 3G and 18 seconds on EDGE.

Of course, Macworld contributor Glenn Fleishman pointed out in his 3G guide last month that comparing 2G and 3G browser and e-mail attachment loading times isn't the most revealing exercise. The most important thing to know about 3G is that data transfer speeds will likely be faster than what iPhone veterans are used to--and more important, that there's room for 3G to grow.

Is 3G available everywhere? What happens when I don't have 3G coverage in my area?

AT&T's 3G coverage map shows the areas where you'll find fast data speeds.

AT&T's 3G network only covers most major metropolitan areas. The company says 3G service is currently available in 280 U.S. metropolitan areas, and the company plans to offer 3G service in nearly 350 metro areas by the end of 2008. If you're in an area without 3G coverage, your iPhone will instead get its data over the slower EDGE network (which has much wider availability). 

For more Mac news, visit Macworld. Story copyright Mac Publishing, LLC.