The USPS has released the final requirements for Tabbing/Glue Standards for Letter Sized Folded Self Mailers. These changes go into effect on January 5th, 2013. For a complete guide to the changes please see link below for reference material for the new requirements.
The main change from the current rules to the new rules is the requirement for all mailing tabs/wafer seals to be NON-PERFORATED and be a MINIMUM SIZE OF 1". In addition, if you are applying tabs to folded self mailers, there is also a minimum requirement of two 1" tabs required on the single-fold, tri-fold and quarter-fold designs that are up to 1 oz (1.5" for over 1 oz). The two 1" tabs can be placed either on the top edge of the mailpiece or one tab on each side edge. There is another significant change with the quarter-fold mailpieces (common for newsletters) that are over 1 oz, these require three 1.5" tabs applied in the same fashion as the current letter sized booklet self-mailers (2 tabs on the lead edge and 1 tab on the trail edge). There are other mailpiece designs in the guide that require 2" tabs for mailpieces over 1 oz.
The important thing to remember is that there is equipment available that will satisfy most of these new requirements.