I actually think it won't be unlocked.
This is 2.0 and 3G, two quite major milestones for the iPhone. O2 has reportedly already lost 7B in revenue due to unlocking and carrier changes within the last 9-10 months. Apple have a contract with O2 to ensure the locking of the device to thier network, at all times, unless originally sold unlocked. Apple are going to put every effort into securing and locking the device down, tight, this time.
As stated above, iPhone OS builds since the seeding of 'Beta 3' (5A240d), have yet to be jail broken or unlocked, which suggests the firmware has been secured successfully, or is being seeded to select trusted developers. The current beta seeding of iPhone OS is 'Beta 8' (5a345), therefore meaning 5 preview builds of the iPhone OS have been seeded, without one having been successfully jail-broken or unlocked.
It is highly unlikely the 'Gold Master' of Firmware 2.0 will be unlocked now.
R-Fly