Lots and lots of new (and sometimes very advanced) stuff, but still - to my knowledge (*) - no simple way to arrange a notebook's text and input cells on multiple columns. It seems that Mathematica can only have a simple linear layout,
| | text | | formula | | figure | | text | | ... | | V
like most books printed in 18xx and 19xx.
- Yes I'm aware one can create cumbersome tables and put text and graphics in different columns. What Mathematica lacks (in my opinion, but maybe I am the only one on Earth thinking that) is a New Kind of Layout. Perhaps a new supercell structure that can accomodate multiple cells (input, text, graphics...) in two or more (simply expandable) columns.
Just wishing. Maybe the Front-end Gods will implement something like that in Mathematica 14. :-]