Because O'Reilly is seen as a pundit, he's being held to a lower standard of accuracy -- even though the questions being raised about where and when O'Reilly was during the Falklands war and during unrest in El Salvador were when he was a reporter.
If I had a favorite of the two, I prefer the Brian Williams piece ("Brian Wiliams’ Other Apologies") but there are parts of "Bill O'Reilly Fights Back" that I like a lot. Or to paraphrase Wayne and Garth at the end of "Wayne's Wolrd":
WAYNE: "Well, that's all the time we have for this blog post. We hope you found the O'Reillygate piece entertaining, whimsical yet relevant, with a revisionist conceit that belied the article's emotional attachment to the subject matter."
GARTH: "I just hope you didn't think it sucked."