Microsoft were upfront about their plans to launch their new Kin One and Kin Two featurephones not only on Verizon in the US but on Vodafone in Europe, but it looks like multiple other carriers are also in line for the QWERTY handsets. According to ROM-tinkerer Conflipper, and his excavations through system provisioning files pulled from an early Kin OS build, AT&T, T-Mobile, Fido and various European carriers are all listed.
Provisioning files basically provide a shortcut to getting phones set up on new networks; they contain configurations for things like 3G APNs, service center numbers and similar. That way, when you slot your SIM into a Kin handset, it should be able to get online and let you take part in Microsoft’s “generation upload” as soon as possible.