Serial Commas

I was taught never to use the serial comma (the comma before the word "and"  in a series of three or more things; also called the Oxford comma).  The hilarious, knowledgable and experienced, Mary Norris, discusses its use very objectively (at the risk of being shunned in the New Yorker elevator—she is an editor there) in the Feb23/March 2nd edition of the magazine. She gives some examples that made me laugh out loud where the serial comma was omitted but had to be inserted:

1. "We invited the strippers, J.F.K. and Stalin."
2. "This book is dedicated to my parents, Ayn Rand and God."
3. "The country-and-western singer was joined on stage by his two ex-wives, Kirs Kristofferson and Waylon Jennings."