It's pretty new at the moment (v.0.0.2) and development was pretty speedy... so I expect a bunch of fascinating bugs coming out. All constructive feedback and suggestions are most welcome.
Done in version 1.0.2! I had to keep the data- attributes as they follow another semantic for my slider... but aria- attributes are added if needed. New demo page contains a demo of aria/keyboard as well: http://lokku.github.io/jquery-nstslider/ .