@Kovid - I've never been called a "Brit" before, ick...
Perhaps I have been swayed by too much reading of USA books/sites and applications like Visual Studio - but it just would never occur to me to use that spelling or pluralisation. To me a dialogue is a conversation, rather than a dialog which is a window that appears on screen. But as I am fairly ignorant to the intricacies of the english language, and I do after all speak a variant from Down Under I am in no position to claim I am right. It just looks... odd.