For the O2 Iphone 3G contract it says you get unlimited wifi at Cloud and BT Hotspots, but how does it work, for the old iphone you registered your iphone's mac address, how does it work with the Iphone 3G?
that's exactly how it works. Been staying in an hotel that had BT. The browser went straight to the log in page, asked for my number and I had instant access for the 3 days I was there. The next hotel had it's own free wifi system and the phone picked that up straight away too.