"It's the belief that only YOU are right."

Doesn't every person who follows a religion believe this though? Their most fundamental, core belief is that their god/s exist and everyone else who thinks otherwise is wrong? To admit they might be wrong in their believe in their deity would undermine their entire worldview, a hard truth to face.

This is perhaps the single biggest philosophical difference between a true scientist and a true believer, and I'm not sure it's a difference that is reconcilable

Well, Stu, I have no doubt plenty of people approach religion like that. but I don't and Joe's post above says to me he doesn't either.
We won't get into formal philosophy if you don't mind, because I think you were using the term informally, but in my view that isn't the important difference: more important is whether you think there is one, complete and invariant way of looking at the world, or whether there can be many, each covering different aspects. And that is not a 'true scientist' versus a 'true believer' difference, but an approach to styles of thinking. Or if you want to put it another way, it is whether I think 'my being right' automatically implies everyone who disagrees is wrong. For religion, in so far as I think I am right, I don't think that means people who think differently are wrong.

This is not really unusual: for the vast majority of things in our life - favourite music, football team (to give Steve's frequent example), art, whatever - we are quite content to recognise that people look at things a different way to us, and while we happen to think we are 'right (in some sense)', we don't think that means everyone else is wrong.

I don't want to turn this into yet another 1000 post thread on stuff covered elsewhere, but I did want to explain to Stu that far from "admitting [I] might be wrong in my belief in [my] deity undermining my entire worldview", it is an essential part of my belief system.