Reduce, Reuse, Recycle. As if our society doesn't have enough solid waste, now there will be more plastic bags filling our local landfills since you have adopted the practice of stuffing our daily mail into a colorful plastic bag.
Yes, the bags are recyclable, but the FIRST rule in conservation is to REDUCE. By delivering a printed postal bag to each residence and business in our zip code, six days per week, the USPS is setting a poor example. These pre-printed bags are another form of junk mail - just one more thing to dispose of each day.
I realize you may save a few moments each day in sorting the mail, but sometimes it is better to be a little less efficient time-wise if you end up saving natural resources. Imagine how much more imported oil will be used to produce these plastic bags WHEN and IF this experiment goes national? I vote that you discontinue this experiment and return to your former, energy-efficient approach.
No bags for U.S.!