Today's the day, as any search marketer not living under a rock for the past few months knows. Yahoo's flipping the switch on its new ad ranking model, so that bid price is no longer the sole factor in determining ad positions. The new ad quality algorithm makes Yahoo more Googley, which they say will improve overall ad quality, and critics say will make Yahoo more money by forcing advertisers to overpay.
The truth, as always, is likely found somewhere in the middle. If all goes well, the new algorithm will improve ad quality, by making it harder for low-quality sites that are engaging in arbitrage to rank well. (That's not to say there are not quality sites that add value that are engaged in arbitrage -- I'm talking about the "made for AdSense" sites that are not adding anything but a middleman). In the short-term, it will also annoy many marketers that have grown used to having a purely bid-based alternative to Google.
The first part of Yahoo's Panama roll-out, the management interface, has raised some concerns with advertisers. You can see discussion of that in the SEW forums, here and here, for starters. There are numerous horror stories of mangled campaigns, inept or unhelpful support staff, and quirky interface elements.
You can bet that Yahoo is crossing fingers, praying, rubbing rabbits' feet, and doing anything else possible in hopes this comes off without a hitch. It's a central piece of their business, after all. According to a New York Times story, Yahoo execs are huddled together in a "war room" as we speak, monitoring today's events.
We'd love to hear about your experience, your complaints, and any tips for your peers in the SEW forum.