@bthall @olivia slightly late to the party here, apologies... I saw those slides too (courtesy of hspter@twitter), and found them fascinating.
However, I'm not really a notebook user, so as an R user I gotta ask - is there a big win over something like a Shiny Gadget/webapp that can be packaged up, shared, and run in RStudio? Seems like that gets the interactivity without some of the headaches... But maybe I'm missing the point?