Going, Going, And Gone?: No, The Oxford Comma Is Safe ... For Now : Monkey See : NPR
Suppose that instead of the list of men our bachelorette met above, things went differently. Without the serial comma, she might say: "The best available men are the two tall guys, George and Pete." There, you really don't know whether George and Pete are the tall guys, or whether there are two tall guys in addition to George and Pete. You literally don't know how many men you're talking about, and while that level of confusion as to elementary facts seems like something that might actually happen on The Bachelorette, it is unfortunate in other settings. If, on the other hand, you use the serial comma, then you would write that sentence only if you meant that George and Pete were the tall guys, and if you didn't, you'd say, "I met two tall guys, George, and Pete."
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Punctuation nazi in defense of the Oxford comma. The advice seems rather misguided to me, though. In the quoted example ambiguity could be avoided with a help from the colon, for instance.
