Apparently there will be no contract preorders for the UKCertainly not from O2...
Probably safest to reserve a pickup from the Apple Store for the 24th, and then you can cancel it if preorders become available! But this way you'll be assured that you can get one on the 24th. This whole thing is so complicated. Why can't the networks just be transparent and give us their pricing now?!
I do find it odd as well that out of O2, Orange, Vodafone, T-Mobile, Three, Tesco & Virgin that ONLY two (O2 and Orange) will be selling the iPhone on PAYG.