The adCenter blog announced ongoing changes being made to how they score ad’s relevancy and quality.

The changes include:

There’s an expanded definition of relevancy, and a higher standard of relevancy required for extremely popular or ‘trending now’ keywords.
In the Landing Page and Site Quality section there’s more detailed definitions
In the Landing Page and Site User Experience section, the following has been added as a scenario that may be considered a low-value user experience.
In the Marketplace Exclusion section there are two new/expanded definitions.

There are more details at the adCenter blog.

I should note, there is a WebmasterWorld thread with complaints about his ad prices soaring recently. He said:

Do you feel the same way? Let us know.

Forum discussion at WebmasterWorld.