A friends phone was half active, could call out and send and receive text, but incoming calls were going to the old phone. After being bounced back and forth between att, verizon and apple she finally got att to fix the issue. Took a couple days.
My iPhone currently says "No Service". Nothing outgoing or incoming. Completely mute. I'm calling AT&T tomorrow or dropping by the store. If it doesn't fix overnight.
Original iPhone took just over 24 hours to get the number ported. It was "activated", I could call out and send messages and use the internet. But any thing received I didn't get until it was complete. AT&T should send you a text when it's done, at least I think they did for me. Make sure your old phone is off and take out the battery or SIM to be sure.
Mine was the same as someone already mentioned...I came from verizon and for a while all incoming texts (except for AT&T) and all calls went to my old phone. I called apple and ot redirected about six times...by then they told me i would just have to wait. Took about 24 hours but that was last Saturday right after launch