Please allow the radio silence, Summer sometimes means holidays!
Slashdot discussed this story last Friday: Massachusetts Plans To Keep Track of Where Your Car Has Been. This is a topic we mentioned before, including when Australia and the U.S. planned nation-wide car tracking systems.
Their summary: "Massachusetts wants to establish a database with the information gathered by license plate scanners installed in police cars. The scanners will scan license plates of every car the police vehicle passes and transmit that information (along with the location) to a database that will be made available to various government agencies. The data wil be kept indefinitely."