Previously had to wait 12 months. Although not strictly a deal hopefully this will help some people as o2 have recently changed their policy.
"You can unlock your iPhone for a one-off cost of £14.69. You'll pay for this from the money topped-up on your phone."
Some people are saying that o2 unlocked their handset for free by giving them either a different persons details whos been with o2 for a while or using details from a simplicity contract