I asked Matt Ashba how the new Plug n Play can be powered. He showed me the the power cord. It has a plug at the end and two different pigtails that plug into it. One of course plugs into Fastrack, hense, Plug n Play. The other pigtail has exposed wires that can be attached to thumbnuts or or other clips that provide power.
The accessories can be powered from Fastrack or any other power source, as always. They covered the bases.