I'm with BNA Flyer. ^ If we're going to be discussing stuff and having extended conversations, then we're going to be calling each other by our first names (at least in the US). If we're at a counter, or a bar, or on the phone only - then I don't want to chat by first names, and there's probably no need for either of us to call each other by name at all.

Isn't it strange how so many people (inc me) have such strong opinions about this?