For bloggers Adsense Publishers who’ve realized the traffic gold-mine inStumbleUpon, it might not be a good mix for you. A thread over at DP (viaSEORoundTable) mentions StumbleUpon as a possible auto-traffic program by Google:Publish Post
It has come to our attention that invalid clicks or impressions have been generated on the Google ads on your site(s) through users of third-party programs paid or provided with other incentives to visit your site. Such programs include, but are not limited to auto-surf, pay-to-surf, pay-to-read, or pay-to-click sites. Please bear in mind that if we continue to detect invalid clicks or impressions from these services on your ads, we may disable your account to protect our advertisers etc…..
Though there’s no definite answer to this issue yet, I believe that this could be a possible reason for an Adsense Publisher to get his account banned (not because there was a surge in traffic but because of the surge in ad clicks caused by that traffic.) This could also be riskier if majority of your site’s traffic are not organic but inflated because of social sites like StumbleUpon, Digg or del.icio.us. Best thing to do is always inform an Adsense Rep when it happens.
