[citation][nom]Silmarunya[/nom]Why all the T-mobile bashing? Are they really that bad in the USA? In most regions of Europe, they offer 100% complete coverage and absolute reliability...[/citation]
That's Europe, where the countries are smaller and more compact. Here in the U.S., T-Mobile has some glaring holes in its coverage (the entire state of Iowa is a roaming area). Its not a bad network, its just not as complete as Verizon (or even AT&T). T-Mobile also only has 3G in major cities (not everywhere like Verizon).
Still, I've been with T-Mobile for 6 years and had no problems. (there is 1 small town of 900 people I drive through daily where I might drop a call, but otherwise coverage is good). They are the cheapest nationwide US carrier and still have unlimited data plans unlike AT&T and Verizon. If you like in an area with T-Mobile 3G coverage, there's no reason not to use them really.
Still, I'd worry about the excess network usage with the iPhone. Sure, the network is good now, but as AT&T found out, the iPhone can kill throughput. Hopefully, if T-Mobile is getting the iPhone, they have taken the usage into account.