This, combined with something I saw in a parking lot yesterday make me think again about electric cars.
I saw a guy text-walking in a parking lot, he nearly hit by a prius which was in low speed electric mode. (yeah that is a user problem, but the guy wouldn't have walked in front of a glass-packed V8 mustang.)
People expect cars to make noise. Television is a decent example since it just happened, but in real life, cars make noise, which warns peds, motorcycles, bicyclists, and other cars that there is 2 tons of metal, plastic, and rubber about to hit them.
Nearly silent, high performance cars remove one of the basest instinct protections we have against current squids driving fast cars (they are loud, so you know they are doing something stupid even before you see them). I imagine some detroit dinosaur who owns a few dozen politicians could latch on to this and require electrics to make some kind of noise.. which will be pretty funny once the hacker/teenager crowd starts modding them.
Mine will probably play Yakkety Sax until I get a DMCA takedown notice,