Melissa Mackey gives us the good, bad and ugly about Google's move to add paid-search ads at the bottom of search engine results, as well as on top and on the side of organic query listings. Before analyzing the findings she looks at performance data for clients before and after the addition of ads. Prefacing the discussion with a few caveats, Mackey tells us what it all means. She writes that conversion rates may fall a bit because of increased competition -- but guess what? That's going to happen anyway as more companies take to online and create search marketing campaigns.