Let me start with some obligatory "site stroking"
Awesome site, I just found it and it definitely helped make my decision to get a iPhone. I will be promoting this site to all my apple friends.

So, I'm a current T-Mobile (US) customer, I have 3 lines but only use 2 of them. I had to add the 3rd when I got my Blackberry Pearl (selling it). So I called to ask about putting the SIM from my 1st line into another phone. I know, but I dont know much about the cell business. T-Mobile said no problems at all, just let them know what kind of phone so they could push (she called them) "Provisions" to the phone. The conversation touched on the iPhone, so I asked if their network even supported it, since it was an AT&T only device. Again, she said they do support it, but let them know so they could push the info to the phone.

The question is, has anyone on T-Mobile actually told them they are using an iPhone? Do they really "need" to push data to my new iPhone? or can I just unlock, add the data plan and go about my business?

Thanks in advance for any help.