Hoping to get an ad on CBS.com, Gamespot, TV.com or CNET? Better call CBS. CBS is expected to announce Dec. 14 that it will no longer do business with third-party ad networks, and will instead sell all of its considerable online inventory on its own.

In doing so, CBS re-opens a debate that raged mostly before the economy declined: Are ad networks good or bad for online media and advertising?

Read More: AdWeek