Come to think of it....I think they maybe just a 3G chip inside the iphone. The chip inside the phone has been "dumb down" to work only as a "2.5G" chip. All Apple have to do is send out a "firmware" update...and there you go you have a 3G phone. Why do I say this? Well, I think this because, remember when Apple starting putting "N" cards in the new iMac and did not tell or posted the information about this? The only way we knew this, is because someone took it apart and posted the information and pictures to prove it. Apple did not say much about the "N" cards until they were ready to release the new airport extreme base station. There was some "noise" about people who had the new Mac, but did not have the new airport, had to pay $4.99 to release the "firmware" in order for the "N" card to work the way it should have. What Im trying to say...Cingular (at the time), about 9 or 10 months ago open up some of its 3G towers in large major metropolitan areas. Keep in mind, they do have 62 million users! There is no way you would just open up the flood gates, to allow this many people or even half amount, to hit yours towers. Remember what Steve Jobs said in Jan at the Macworld show, that the hardware is there....all you have to do is software updates. In addition, AT&T sells 3G phones at there B&M stores, and their web site, in NON "major metropolitan areas" where as you can only use the 2.5 G spectrum....think about it!
http://www.wireless.att.com/learn/why/technology/3g-umts.jsp
https://www.macrumors.com/2007/01/09/apple-quietly-releases-802-11n-capable-airport-extreme/
http://phobos.apple.com/WebObjects/MZStore.woa/wa/viewPodcast?id=212293773&s=143441
http://www.wireless.att.com/learn/why/technology/3g-umts.jsp
https://www.macrumors.com/2007/01/09/apple-quietly-releases-802-11n-capable-airport-extreme/
http://phobos.apple.com/WebObjects/MZStore.woa/wa/viewPodcast?id=212293773&s=143441