I should have written down which book I saw this in, but it was late last night and I was tired. I'll look for it again later, but I didn't want to forget to make a note of it anyway.
While strolling through some of my many Kindle books, I came across one that had a note at the beginning to the effect that the author is British and the book uses British spellings -- honour, centre, realize -- which are NOT errors.
Didn't we sort of used to just take that for granted, even before the whole "global community" thing? Or have too many readers become so U.S.A.- centric that they think everyone who doesn't adopt "our" spelling is automatically wrong? Are they so culturally isolated that they don't even know there's a difference?