
adCenter is the name that Microsoft has given to their PPC platform. It was developed much later than the Google and Yahoo PPC platforms and tried to focus on providing enhanced tools for marketing managers to better focus their PPC adverts.
Although the adCenter platform has been pilloried by some, we have always suggested any website should explore how it can help achieve their goals.
Managed correctly Microsoft's PPC offering can deliver very high quality clicks, so even though there may be less clicks available on this platform you may find that it could be your most profitable advertising channel online (as we have for some websites).