Budfrump2I'm in NYC and plan on using these. I don't think there's anything in the law restricting the use of these guys. Most of what I read seems to only address gas powered vehicles(all prohibited unless registerable) and electric bikes which are limited to 750W or 1HP and travel no more than 20MPH.
http://www.nycewheels.com/ecoreco.html http://www.nycewheels.com/ecoreco-m5-electric-scooter.html