Just spoke to someone direct at o2 and they wouldn't give me a concrete release date to upgrade to it via them. The only thing she did say was that it would be available by the end of next week, so I guess o2 have been hit by the same delays as most others.
I don't mind waiting a week but I wish there were more concrete dates being set down.
Edit: But someone on xda got this response:
So many mixed messages.
I had the same type of mixed messages when I was trying to get my Galaxy Note. Rang around quite a few CPW and Phones for You shops each one giving different answers. Some stores hadn't heard of the Galaxy Note and had no idea when they'd be getting them, others confirmed they would be stocking them, but it'd be in a few weeks and another told me only the high profile "flagship" stores would be getting them on release and suggested I ring some of them. Managed to find 2 at the Phones for You in the Trafford Centre and they had them from release day (Third of November).
It might be the same case with the Galaxy Nexus, where only the larger/higher profile stores are getting them on release day in small numbers. None of the network shops at the Trafford Centre had any notes either, just CPW and Phones for You who had a total of 5 between them. Quite a small amount considering it was a new release that day.