The issue of the Oxford comma has come up several times at Language Log, with some very amusing examples of the consequences of omitting the comma before and. See this magazine cover, the October 2010 issue of Tails, isn't just missing the final comma but all the commas in the series.

It reads (linebreaks original),

EAT,
RAY,
LOVE
Rachel Ray
finds inspiration
in cooking
her family
and her dog

It appears, given the indignant assertions of the Tails editor that the commas were photoshopped out, but still, it had me snorting my coffee this morning.