I loathe the Oxford Comma. Its presence in written texts is highly irritating, inept, inapt and unnecessary (note the absence of one of the little blighters after "inapt"). But then, I suppose I'm one of only a very few who gives the proverbial "continental" about such arcane matters.
What, you may ask, is the Oxford Comma?
The graphic explains all. It concludes that if you live in the United States, then you can use it with a clear conscience. This is wrong. You should never use it: period. Not even in Texas.