Most people here are asking for more features. Please be careful with that; it would be a pity to see such a pearl to swell into bloatware. You have very good taste, let it be your guide.
I can't speak for what they've done since I stopped using them, but looking at their homepage, the velocity still seems pretty high.
Used today's commute to package it into introjs-rails, for anybody that wants to use this in their rails app (assuming you are using the RoR asset pipeline)
gem 'introjs-rails'
I can link you to my project if you'd like to see how I use it. Just email me- mariusz.n.lapinski@gmail.com. My app isn't ready for prod just yet.