Took this from the telegraph newspaper online
"As part of the shake-up, which is designed to help Apple shift 10m iPhone handsets globally this year, O2 is expected to offer the first pay-as-you-go version of the iPhone, and to force contract customers to sign up to the network before leaving stores with the phone"
So you could just buy a "pay as you go" and walk out with the handset too then?
"Apple also wants to prevent contract customers "unlocking" the iPhone for a small fee at specialist mobile phone shops and inserting the SIM card from their existing provider into the handset"