The news that Yahoo's Overture division will divorce their contextual ad service, Content Match, from their traditional paid listings service makes perfect sense. Just like Britney's short-lived Las Vegas marriage to her hometown friend, sharing roots is not a sufficient reason to tie the knot or stay married. Overture's Content Match is a by-product of its core search engine paid listings offering (as is Google's AdSense). But, as Overture's VP of partner product marketing, Paul Volen, says "...it's a different experience", and "advertisers ... would like to control it separately."

Along with the obvious differences between bidding for a listing on a search results page and bidding to place an ad on a undetermined "contextually-relevant" destination Web page, the two services differ in terms of their stage of evolution and competition, too. Contextual ad services are just emerging and will become more specialized and better targeted as ad-serving firms refine their technologies and build appropriate networks of advertisers and destination sites. Improved ad formats, more useful ad content, and personalization capabilities will all contribute to a better return on contextual advertising. To compete in the contextual ad arena, Overture (and Google) will need to differentiate their product offerings and level of service to the advertisers that want to optimize the return on their online ad expenditures. Given the current and predicted high rates of growth in online advertising, it's a safe assumption that we'll see lots of improvements in the contextual ad programs from Overture and Google.