Yes I know I'm one of the Jupyter dev :-) there is still a difference in notebook format and protocols. In that sens JupyterLab is not more compatible with Rstudio than the normal notebook.
Lol, sorry - well hopefully someone else reading this thread can find out about jupyter lab. it really is amazing.
Thanks so much for all your hard work!
It's in alpha right now but they're making crazy fast progress on it. I've been using it and it's awesome