West coast US views of the carriers ...
AT&T and T-Mobile both use GSM, but there have been rumors that while AT&T's is compatible in Europe, T-Mobile USA uses an offbeat frequency not compatible in Europe.
AT&T you only use if if you want an iPhone, their customer service is horrific (not to mention their complete willingness to violate constitutional privacy rights (and the recent FISA bill gives them immunity from prosecution)), coverage is okay, but they drop calls left, right, and center. 3G iPhone customers regularly complain about getting better reception turning their 3G off and using 2G service.
Verizon is popular, decent coverage, decent customer service (for a cellphone company - cellphone companies in general rank below cable companies, Verizon is just the lesser of the evils).
MetroPCS just plain lacks coverage. And Sprint drops calls so often, they made it part of their logo. Sprint also seemed to be the worst hit by the recent financial crisis, several papers reported they were hemorrhaging customers faster than any of the other cell companies.
[and that has been my weekly rumor-mongering
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