Energize said:
The us uses hsdpa and 3g.
Everyone's getting a bit confused here between the phone standards - there's a hierarchy which people don't seem to be recognising. At the top layer there is 2G and 3G - that is based just on data rates not on technology/frequency or anything else. There are 2G and 3G networks all over the world.
There are lots of 2G technologies and frequencies those technologies are deployed in, for example GSM is a 2G technology and it can operate at 850, 900, 1800, 1900MHz (the downlink band). In Europe we use GSM 900 and 1800 as our 2G technology. These are also other 2G technologies that have nothing to do with GSM like IS-95 which uses CDMA rather than TDMA. Japan have their own 2G system called PDP and the Nextel system in the US uses yet another (iDen). All different 2G technologies.
Then there is 3G again with different technologies. In Europe we use WCDMA (FDD and TDD) but there is also the CDMA2000 family and the Chinese have the own thing called TD-SCDMA.
So within each technology there is another layer of detail. With 2G, GSM, we have EDGE (it's still GSM, just a slight physical layer evolution of GSM). With 3G, WCDMA we have HSDPA, HSUPA etc as evolutions. The CDMA2000 technology has 1x, 1xEV-DO and 1xEV-DV.
So what's the iPhone doing? In the US Cingular are a 2G-GSM and 3G-WCDMA network, same technologies as Europe which makes them the perfect partner. However the frequencies in the US are different to Europe so the same device won’t be used. I've no doubt the next iteration of iPhone will use 3G-WCDMA, both in the US and Europe.