Relevancy Ranking
Relevancy Ranking- Surprise Winner: Yahoo (because they haven't gone overboard)
Hats off to Yahoo here. Like Google, they include historical clickthrough rates in their ad-ranking formula. Like Google, they also include some measure of how relevant and related the keywords and ads are. Neither company discloses the exact weightings. Google's formula is more sophisticated in the sense that a variety of editorial priorities have been built into the "black box," whereas Yahoo continues to address more of these issues with human editorial control and/or overt editorial rejection messages. In designing their latest-generation ad platforms, both companies have been inspired by some of the notions of quality and relevancy that apply to organic search. It's not for the faint-hearted advertiser, but it's improving the search experience, and that's a win for everyone involved
Usability - Advantage: Google. But Huge Improvement for Yahoo
Google's interface tends to be easier to navigate than Yahoo's. Yahoo's interface requires more clicking to complete account-related tasks. For example, in Yahoo, advertisers cannot set unique bids for multiple ad groups on one screen. Advertisers need to go to each ad group to make bid changes. In Yahoo, it can take more time to complete campaign related tasks.
Conclusion - The Winner: Google (for now at least)
The winner and holding champion: Google AdWords, naturally. But Yahoo's Panama has a good cutman in its corner, a big entourage and is looking pretty for the after party (if not the rematch).
Next: How we got here