Using the Oxford Comma

I didn't know that it was called the Oxford Comma, but I've been in love with it since Dr. O's Editing II class for The Collegian. It is the second comma used in a series of three items. And it helps clarify writing. I require it for my middle school, high school, and college students (see there). So does the Associated Press (not that I write for newspapers anymore).
But two years ago, an ironic twist came when the University of Oxford PR Dept. changed its style guide to eliminate the Oxford Comma! Many opinionated Tweets ensued. Oxford itself kept the Oxford Comma.