Well, I've had a bit of an issue ordering one so far...
At 12:30 last night, I got an email from Apple that my reservation was ready to be filled. But when I tried to order the phone it said my AT&T account couldn't be upgraded. So I went to AT&T, and sure enough I could order from them, so I placed my order.
However, this morning I had an order confirmation email from AT&T that said my phone was shipping between 10/21 and 10/30.
So I tried my reservation at Apple again, and now it's coming back as eligible. So I called AT&T to cancel my order, and the guy on the line told me their system didn't have my order/upgrade in it yet so all I have to do is decline the Terms and Conditions email I'll eventually get from them to cancel my order. In the meantime I placed my order with Apple, so that should ship out in the next day or so.
Something tells me I'm about to end up with two iPhones... and they're both going to be tied to the same phone number.