Originally Posted by IceTrojan
What is the default title when addressing a prof with a PhD... "Prof." or "Dr."?
I find myself having to do a bit of research before meeting one, to see how they refer to themselves in their bios. I'm around 50/50 in how one addresses oneself.
(Some, I'd like to address as "DB"

)
The only people who get offended, in my experience, are Professors of Medicine in Europe and Asia (specifically
not in the US). They are offended when you call them "Doctor" instead of "Professor."
And, yes, there is the strange case of the UK. There, surgeons who become members of the Royal College of Surgeons revert to being called "Mister." They may be offended if they are called "Doctor."
People with PhD's may prefer one or the other, but I've never seen one offended unless they correct you once and then you persist in using the wrong form.