I was always taught never to use a serial comma, and never have. Glad to see the People Who Are In Charge Of Such Things came around to my way of thinking. :D
That said, unneeded punctuation can lead to grammatical aberrations such as: “Angry constituents told United States Senator, Harry Reid, to go jump in the lake.”
Eschew unneeded commas. Your keyboard will thank you.
Except for that one. :)