Here is a link to the final ruling regarding the ELD Mandate.
Just a warning its 126 page pdf. If you are on a data plan you may want to wait until you get on wifi to look at it.
Some good stuff in here though.
Authorized safety officials who conduct roadside enforcement activities (i.e., traffic enforcement and inspections) or compliance safety investigations will be able to select a minimum of one method of electronic data transfer from each type of ELD. States will have the option of choosing a minimum of one ‘‘telematics’’ electronic data transfer method (wireless Web services or email) and one ‘‘local’’ electronic data transfer method (USB 2.0 or Bluetooth) for the electronic transfer of ELD data.