Serial commas

Rico says the thing he rewrites in almost every purloined post, whether from a publication or another site, is the lack of the use of the serial comma.
What's a serial comma, you ask?
That's the one that comes after the penultimate item in a list like this one: the first thing, the second thing, the penultimate thing (followed by its proper serial comma), and the last thing.
Why is it important, you ask?
Rico says he will use this example (courtesy of his friend Rani Cochran, lo these many years ago, back when Rico didn't even work for Apple yet), a real acknowledgement from a real book:

I want to thank my parents, Ayn Rand and God.

That would read a little different with a serial comma, wouldn't it?