Specifically, the subscription plus registration turns off:

* The top banner ad next to the logo

* The right sidebar “skyscraper” ads

* The two Blogads slots in the right sidebar

* The 300x250 ad after the first post on the front page, and after the post on each individual page

* The Amazon interstitial ads

* The bottom Amazon banner

* The “partners” ads at the bottom of the left sidebar

* The “sponsored links” at the bottom of the right sidebar