O2 has just let us know that (by lunchtime) the iPhone 3GS has already outsold the opening days sales of the iPhone 3G in the UK.

We did take a wander down to the Apple and O2 stores this morning, and can confirm that even in a relatively small city, the queues were really quite big.

Footfall to the O2 stores was 10x that of a normal day, with the online store seeing a 100% increase in traffic.

Another little bit is that the Black is outselling the White by 3:1