I wouldn’t put too much emphasis on that single picture. It might even be a CAD rendering from hints I see, and therefore could be missing any number of details and be inaccurate.
The rumor i heard that is semi wireless. No wire from the shifters to the derailers, but the derailers share a battery, so they will have some sort of wire. Totally a rumor, could be just a guess
They will be extremely useful according to the marketing department! Those changes will probably save you 5 minutes when riding at 40mph on a 10 mile TT
Charge port on the rear derailleur, both the RD and FD connected to the battery using the newer (smaller) EW-SD300 wires. The Junction A is gone, it’s part of the rear derailleur now :).