3 is offering the full gamut of options, with postpaid plans, extra data packs for heavy users, and standalone phones for use with prepaid. On 24-month contracts, you can choose between $39, $49 or $79 caps, but you’ll pay an extra per-month charge for the phone on everything except the $79 cap, and even on that option you can’t have a 32GB model for nothing.
The extra data packs (priced per month and only available with a new phone) cost $6 for 500MB, $10 for 1GB or $20 for 3GB. The latter seems a reasonable deal if you plan on tethering.
At $929 for the 16GB 3GS or $1,129 for the 32GB, outright prices are again a little higher than from Apple itself.
3 is also allowing customers who pre-registered for its deals to buy the phones on July 16, while existing customers can migrate their existing plan to an iPhone for between $35 and $45 a month, depending on model. (This is a lousy deal for an older 3GB iPhone, frankly, especially if you’re near the end of your contract, but OK for the newer 3GS models.)
Overall, none of the plans are astonishing, but for users already partial to 3 they represent reasonable value on a quick analysis. So far, the 3 plans haven’t shown up on the handy iPhone plan calculator, but we’d expect them to appear there soon.