To comma, or not to comma . . .
That question has been debated among writers for some time. Since a comma is used to replace the word "and" when listing several items in a sentence, must one use a comma before the last item listed even when there is an "and" before it? Example (with the debated comma): I bought bread, apples, and peanut butter at the grocery store.
Over the years, the University of Oxford Guide to Style has insisted upon including the last comma in this situation. The serial comma has become so identified with the university that it is known as the "Oxford comma." Oxford's position has been echoed by the Chicago Manual of Style, Elements of Style by Strunk and White, and the BBC. (Thanks to the Oxford comma, you know when reading the preceeding sentence that Elements of Style is by Strunk and White, not by Strunk, White, and the BBC.)
Others have disagreed about the necessity of the final comma. The AP Stylebook, for instance, says that the comma before the last item in a list should be omitted unless it is necessary for comprehension. The AP Stylebook is primarily intended for journalists, but we have seen that journalistic style has a way of entering the mainstream. Consider, for example, the greater acceptance of the use of "alright," when traditionally (and more correctly) it should be written "all right."
So when word came out that the University of Oxford was abandoning it's own comma, punctuation nerds felt the ground shake a bit. Cries of angst arose on Twitter and Facebook as people tried to make sense of it all. It took several hours before it became clear that only the public relations office at the university had changed its guidelines for press releases to journalists, having no affect whatsoever on the advice offered in the Guide to Style.
So grammar geeks can heave a sigh of relief. Their Oxford comma is safe. Everything, it appears, is alright.