21CPW.com has posted a copy of the list of processing facilities set to be considered for closing by the USPS. The list was apparently faxed (is the USPS the only company that still faxes things?) to the unions yesterday at 5PM.
Note that there are multiple consolidation options listed in some cases. For example, each of the three plants closest to Boston is listed as a candidate for consolidation into one of the other two. Presumably at least one of them will remain open.