Nissan does not do OTA. Software updates appear via technical bulletins, NTB, and do not occur that often. Dealerships install them. Usually they appear in response to specific problems, e.g., air bags, 3G modems. It is not like an app update process. Do not expect any updates for services like navigation or entertainment. Maybe Nissan sells packages for those items. If you ever get close to a battery warranty milestone, have your Leaf checked early for NTBs. Some drivers barely made the benchmarks and then found the Leaf lacked an update that affected battery data. They had to get updated and wait a few days for the update to generate valid capacity results.
2013 SL Blue Ocean
Bought used, March 2015 12,764 miles
4th bar drop 56 month, 20,200 miles, AHr at 42.1
Appears fully loaded
Condo home, Using public charge except in emergency
Dallas, TX downtown, shaded non-temp controlled garage