Using a US iPhone in the UK
Of course you'll need to get a UK SIM (unless you're keen to pay roaming charges on the AT&T contract it came with). With most phones, this isn't a problem; but with the iPhone, who knows? The device will probably have been locked to US network AT&T. And although it should be possible to unlock it - many dealers will do it for a small fee, if they can - it's not yet clear what sort of protection Apple may have included on it.
We know that users will have to register it using an iTunes account , possibly enabling a further level of lock-in security. iPods have never made a point of being user-modifiable and so it's likely to be the same with the iPhone. Someone will figure out a way to crack it, but it'll probably cost you - and it may take some time too.
Are you being served?
The high demand and hype for the iPhone, and the expected exodus from virtual and real-world shops on 29 June, will be followed by the inevitable surge in service enquiries.
This means that even if you do get your iPhone quickly, you may have to wait to get it to work satisfactorily. Queries through official channels are likely to be bogged down. And you can forget about advice from Apple about using the iPhone with UK networks - at least until the still-unspecified European launch towards the end of 2007.
The first incarnation of the iPhone in the US will not have a 3G internet connection. Instead it'll use the 2.5G equivalent EDGE, which is popular in the US but hasn't been employed by any network in the UK. So your iPhone browsing experience will be limited to standard GPRS - glacially slow if you're used to using a 3G account. Just as UK networks are upgrading to even faster HSDPA, you'll be back in the virtual bus lane.