O2 should have it next week (from 8th September) but it might be only available on Business Tariffs initially.
Unlocked SIM free models are now also available from a number of on-line resellers.
If you do a search on here for 'O2' and 'UK' you will probably find a few more answers also, but I don't think anyone really knows for sure until it actually appears.
I am waiting to use it on O2 also!
Last edited by Montala; 09-04-08 at 07:03 AM.
Reason: Clarification!