Reading the comments, there seemed to be a pattern between the two camps. The people who were against the Oxford comma were looking at the comma syntactically as a replacement for the conjunction,
I believe the people for the comma were approaching the problem phonetically–this is where I would pause in speech to denote a new item in the sequence, therefore a comma is correct.
Or maybe I’m wrong.
Oh, and for reference, here’s the original article that sparked the debate, and while I believe is correct in every possible way.