In case you are not aware, the new release of AVG anti-virus software, free and paid, includes a "Do Not Track" add on/plugin for your browser. Personally, I like it, not only does it block all analytics, it is also capable of blocking social sites, ad trackers, and so on. The default list includes:
Analytics - Comscore Beacon Facebook Connect Google LinkedIn Yahoo
Social Networks and plugins - Facebook Social Plugins Google +1 LinkedIn Button Twitter Button
Ad Networks - 24/7 Real Media 33Across [x+1] Accelerator Media AddtoAny Adition AdReady Aggregate Knowledge Baynote Observer Bizo Brightcove Brilig BTBuckets Collarity Connextra Criteo Crowd Science Dedicated Media Didit Blizzard Dotomi Etology ewaydirect Fetchback Gunggo IndieClick iPerceptions MyBuys NetSeer Nooked OrangeSoda Reinvigorate Resonance Spot200 Veruta ViziSense WidgetBox Ybrant Media
It also shows the number of services being blocked per page and who they are. And while the user can adjust the setting to allow/disallow, I suspect many may leave the defaults which basically blocks everything but the social links. While this is a boom for privacy advocates, I can see it having a negative effect on ad revenue and accurate analytics.