It's been a couple of years since I played around with Jupyter notebooks, but then I got frustrated quite soon:
Stepping outside my preferred editor (vim) was annoying, likewise I had no idea if (how?) I could export the code out of notebook to a regular .py text file (without clumsily copypasting each cell). And the .ipynb files itself seem quite terrible to manage in Git: write something and if you want to 'git diff' the changes, sometimes what you see is okay, sometimes it's not very... easily decipherable. (Text encoded image/png's?!)
My preferred workflow with R is to open the files I'm working with in both RStudio (with vim keybindings) and vim. Maybe if I just strictly restricted the use of notebook cells just for calling scripts and functions written in external files, and use the notebook as a whole just for presentation purposes, but then it wouldn't be that much an improvement over regular IPython. Any thoughts?