n January, Fox News had its worst primetime ratings since 2001 in the all-important age demographic of 25-54, according to new Nielsen data. Furthermore, its total day ratings for the age group fell to their lowest levels since 2008. The grim news for the conservative cable network was gleefully publicized by liberal rival MSNBC, which boasted a 20 percent boost in the 25-54 demographic from the previous year, and an 11 percent climb in primetime.

What happened? While some liberal commentators would like to see Fox's decline as evidence of a leftward shift in public opinion, coinciding with President Obama enjoying his highest favorability ratings in three years, the truth is probably simpler. Conservative viewers in January — participating in a collective version of see no evil, hear no evil — likely passed on watching President Obama's inauguration, a ratings bonanza for MSNBC. Fox has suffered similar ratings declines during other big Democratic events.

It's also important to keep the latest development in context. As Katherine Fung and Jack Mirkinson at The Huffington Post note, "Fox News still had nine out of the top 10 programs. It has spent 11 consecutive years as the top-rated news channel. Its 6 a.m. show drew almost double the ratings of CNN's top-ranking primetime show."

Ouch. However, while Fox may not feel the need to shake up its lineup à la CNN, the house that Ailes built is making a few changes. Sarah Palin was recently let go as a commentator, while Red State editor Erick Erickson, a recent refugee from CNN, was brought on board.