UK iPhone owners subscribed to O2 will indeed be allowed to unlock for other carriers, according to the CEO of O2's parent company, Telefonica Europe. "Once the iPhone becomes available on other UK networks," says Matthew Key, "we will allow O2 customers to unlock their iPhones, although of course they will still need to honour any outstanding contract period they have. At the end of their contract period, they are entirely free to move to another operator -- though naturally we hope they won't want to!"

Orange is set to begin carrying the iPhone on November 10th, while Vodafone will join sales in early 2010. O2 has had exclusive UK rights to the iPhone since 2007, and until now has not needed an unlocking policy, or formally announced one. It is common for companies in regions with multiple iPhone carriers to allow switching services if there are no contractual obligations.

Key meanwhile admits that O2's network has been "under pressure in parts of London," specifically where there are high numbers of smartphone users. Largely as a result of the iPhone, overall O2 data traffic is said to have increased 18-fold in the space of a year, continuing to double every three months.

"We are constantly increasing the capacity of our networks and the good news is that we now better understand and know what fixes we need to put in place to improve our levels of service," says Key. "Fortunately, it's not about needing new mast sites and we are investing more than £30 million to address capacity issues in London alone between now and Christmas and I'm confident that we’ll see much improved levels of service as a result."