Well,
No iPhone for me. That is, no iPhone service for me, since I already have an iPhone 3G.
The South Korean phone system works like this (from what I understand):
The phone companies here control all phones on their network. That is, every phone is registered on the networks here. The only phones they allow to be registered are Korean phones. Therefore, no iPhone service for me.
I could of course somehow change the IMEI on my iPhone to a South Korean IMEI, but that's highly illegal, and due to S. Korea's insistence on being different from the entire developed world, I wouldn't be able to use text messaging here.
I spent $800 just getting the phone. That's $399 for the phone itself, and another $400 (plus taxes) getting out of my contract with Rogers. Yes, that's rape, I know.
So I've got the fanciest iPod touch in all of Seoul. I even bought a SIM unlock chip. I got it today, after waiting 3 weeks for it to be shipped here.
So there you have it folks. They (and Rogers) have no problem charging me $3/minute for roaming, with data, call display, visual voicemail, and SMS all working, but they won't let me 'register' my phone and use it as a local phone here.
I've recruited my Korean friends to help, and they have all found the same information. I couldn't believe it. I can't use my phone here. I've looked into the Samsung, LG, and other high-end phone lines here, and they're nice, but they don't work with iTunes, and they just don't zip the way the iPhone does.
There are rumors of the iPhone coming (and not coming) to South Korea abound, but nothing official from Apple or any of the providers, so I won't hold my breath.