The k700i is a GSM phone, so your choices for the most part are limited to Cingular and T-Mobile. (maybe a few regional carriers I’m not familiar with) Just take the SIM card they give you and stick it in the k700i. Cingular probably has better coverage, but T-Mobile’s been good to me. Probably because I’m not Paris Hilton.
Also, how could I (possibly) get Cingular, T-Mobile, or AT&T to pay for my early termination fee? I hate Verizon b/c of their b.s. $80 internet plan and the GPRS/EDGE thing would work great… (i would plan on buying the W800i seperate if i must…)