• http://joeduck.wordpress.com JoeDuck

    Nice summary of a complex topic Mona! A burning question for me on all this is how much of the total advertising spend is from PPC arbitrage (ie bidders on tens of thousands of terms who hope to get somewhat higher bids on their own ads) vs affiliate website PPC vs PPC for a product provided by the advertiser. Have you seen any studies of this?

  • http://www.rimmkaufman.com/rkgblog Alan Rimm-Kaufman

    Even before yesterday’s quality-based bidding rollout, we noticed that Yahoo regained a small bit of ad spend share from Google in December and January, possibly due to how clicks were allocated between the old and the new platform during the Panama migration.

    Graphs here:

    http://www.rimmkaufman.com/rkgblog/2007/02/05/panama-60-days/

    and here:

    http://www.rimmkaufman.com/rkgblog/2007/02/06/panama-60-days-part2/