First of all, what a great ideia. I love the plugin!
But isn't navigation "reversed"? Unless in USA the navigation occours like so by the plugin (left=forward; right=previous), at least here in Europe (Portugal) the right arrow it's for when we want to go forward and the left arrow it's for when we want to go back (previous).
I will try to change the code to match right=forward;left=previous, but in anycase, maybe in a future version something like this could be considered as an option. It would mean having to build a settings painel, but i think it would be worth.
In any case, great plugin :)