I don't know how much truth there is (if any) in this, but someone on another forum has said that O2 have cancelled all the orders placed and are ringing the people who ordered them to tell them why - That is 'if' you put a legit phone number in.
I ordered mine on Saturday for delivery today, but yesterday I got the 'passed to despatch' and the 'out of stock' emails. So I won't be holding my breath. I suppose it is possible that they are genuinely out of stock if this has been all over the internet, however, it's more likely that O2 have noticed whats going on and cancelled all the orders as stated above.
The way I'm looking at it is, if they deliver, all well and good, if not, it was worth trying anyway.