I'm getting my iPhone on Tuesday 
What I want to know is.... I can use my home wifi when I'm at home, I also am signed up with The Cloud, but there's not many places that have that, and o2 wireless (my network) isn't really available in many places yet (although apparently they'll have a large network by 2013).
I notice BT Openzone has a large network, I'll be able to wifi pretty much anywhere, but costs £5 a month.
So what do others do about wifi when out and about?