Dead Tree Edition (a blogger I stumbled across when I was looking for consolidation in book printing) does a lot of USPS coverage, primarily from a magazine/catalog production/distribution perspective.
While I would not say I agree with the blogger on everything, I have found that blog to be consistently informative on topics that are probably important but very, very poorly covered elsewhere.
Reading (for the purpose of mocking) e-book coverage for the last couple of years was a real eye-opener to me. I had not fully understood just how hollowed-out printed reading matter had become as an industry -- it still looked pretty good. It turns out that the postal service has some of the same characteristics.
I feel bad for the postal service. It's sort of the government corporation version of what happened with the railroads. They were not actually allowed to be run as a business, because there was so much regulation regarding service and pricing. The railroad situation was worse in some ways in that people sort of expected them to be endless pots of money. The expectation is not now and never has been that the USPS would be a source of endless revenue, but I think there has been an unbounded service expectation. This expectation has encouraged both political parties to do slightly nutty things, because their constituents are even nuttier.
This entry is a particularly good example of how out of control this got over the decades:
I had _never_ heard of special treatment for the Wall Street Journal and other publications at a significant cost to USPS. This is just disgusting.