In fact, there is a GAO´s paper ("US Postal Service: Key Reasons for Postal Reform") that put as one of the main areas that needed addressing by the Congress the following: "Flexibility and Oversight: Congress needs to balance increased flexibility for the Service—through streamlining the rate-setting process and allowing a certain amount of retained earnings—with appropriate oversight by an independent regulatory body to protect postal customers against undue discrimination, restrict cross-subsidies, and ensure due process. In addition, the Service needs additional flexibility to rationalize its infrastructure and reshape its workforce. Any such additional flexibility should be accompanied by appropriate safeguards to prevent abuse, along with mechanisms for enhanced transparency and accountability." (sorry for the long citation) Worldwide, postal service operators are streamlining their cost structure, eliminating cross subsidies and prepairing for increased competition. As sorting is one of the main cost factors in postal operations, it makes sense to reflect this in smaller tariffs for big operators that pre-mail their correspondence (I´m reasoning in abstract, since I didn´t read the real plan). By the way, with all the hype around the diminishing of distribution costs using internet, I bet that many of these smaller publications would profit of moving to internet-based only publishing.