Purchased mine just now, called home as I left the Apple store
Sounds like O2 are really not looking after their "first day" customers. Popped into my local Apple store just now and purchased one, and apart from them having to do my URU check by hand (servers down again) it was all working by the time I left the store.
Did O2 really not plan for so many people wanting one, even after they got such a large response to their pre-registration.
(Happy face - as mine works)