Remember AltaVista? The search engine, long swallowed up by Yahoo, once hired professional trashy babe Pamela Anderson to win our affections. What that terrible TV ad tells us: TV ads don't build Web brands.
Need more examples? Here are commercials from MSN, Yahoo, and Ask.com. (I found them using Google and YouTube, a Google-owned video-hosting site.) Do any of them articulate a reason to switch search engines?