AT&T CEO Randall Stephenson told a group of reporters at the Churchill Club in Santa Clara that an iPhone capable of operating on the company's 3G HSDPA network (and presumably other 3G networks) will be available sometime next year. You can hear Stephenson's comments in a recorded Webcast of the event.
Responding a reporter's question about a 3G phone, Stephenson said "You will have it next year."
Earlier this month, an obscure blog post on SevenClick claimed that Spanish carrier Telefonica plans to carry a 3G iPhone next year. In a very brief conversation with a Telefonica manager, SevenClick asked if a 3G version of the iPhone would arrive in Spain by next May. The manager replied, "Yes! They expect it."
In August, AT&T sent a survey to iPhone customers inquiring about various functionality, including 3G.
Being classified as a "3G" network does not guarantee any specific throughput level. Housed under the 3G umbrella are various actual transmission methods with widely varying speeds. Currently, the highest speed 3G American cellular networks include those that use EV-DO technology (Verizon and Sprint) or HSDPA (AT&T/Cingular) networks. 1xEV-DO can deliver theoretical speeds in the neighborhood of 3 megabits per second, while HSDPA can theoretically deliver up to 7.2 megabits per second on select networks.
Real-world performance statistics are, of course, almost comically different from the inflated theoretical speeds. AT&T/Cingular quotes ?real-world? download speeds 400-700 kilobits (about 88 kilobytes [KB] per second per second for its HSDPA networks, while Sprint quotes about the same for its "Rev A" EV-DO networks. A few tests, however (like this one from Bare Feats on Verizon?s network), have shown real-world speeds of up to 1.8 megabits per second. At the maximum quoted speed of most readily accessible 3G networks (~700 kilobits per second), a 1 MB file would take about 12 seconds to download.
3G coverage, relative to 2.5G, is scarce. AT&T/Cingular offers a pop-up coverage map exhibiting the disparity. HSDPA coverage is not nearly as comprehensive as that offered by EDGE, but is expanding quickly beyond major metropolitan areas into smaller cities. There are also large blind spots in purportedly covered markets -- more than are apparent than with AT&T's EDGE networks.