Mike Steinbaugh points out that the rise of Firefox might actually result in the fall of Adsense. The adblocking technology built into the new Firefox is having an impact on Mike’s AdSense revenues.
If this is in fact the reason why my Adsense revenue is experiencing a steady decline, Google is going to start losing advertisers. This effect would take years since Google is so hot at the moment. However, ad delivery is the core money maker for Google.