Long time lurker here! Definitely have problems with the wifi connection on the iPhone 5. Ran speed tests on both iPhone 4 and 5 and, in the room that contained the router and both had d/l speeds of about 7.5mbs. But in the next room, the iPhone 5 was down to 0.5mbs while the iPhone 4 maintained the 7mbs speed. Rang Apple support and, after disabling the security on the router and restoring iOS6, they said it was a hardware issue and to return it. Tried exchanging it with the Three (UK provider) and they don't think they'll have any spare stock until 20th October(!) so have an appointment with an Apple Genius on Saturday. Just hope they have a spare iPhone with a good wifi chip in it!