I did something almost exactly the same[1] for a design project at school a while back, where I explained why current infinite scrolling UX is not great and how something like this could help[2]. I'm glad someone made this into a library!

[1] http://newcoursys.herokuapp.com/courses/2012sp-cmpt-165-c1/a... [2] http://newcoursys.herokuapp.com/#marking-interface