Played with it during Advent of Code. It really disappointed me. The first 10 minutes of discovering the language were great--in theory it had so much potential between how errors automatically propagate up, the extensive library, and metaprogramming abilities of the language. The syntax is unconventional and to a certain degree off-putting (coming from a person who doesn't mind Erlang, Prolog, Lisp, Forth, Haskell, ...) but usable. The novelty starts to fade when you realize how poorly suited it is for general purpose programming. Despite having features for everything, it's hard to make them all connect. I spent hours trying to figure out how to use the DFS functionality in remarkably simple ways, for example. Maybe it was the documentation that failed me, but that doesn't really help sell the language either if that's the case. I think if Wolfram actually cared to "come down to earth" and think about users it could be a great language--the potential is definitely there--but right now it really looks like he jumped the gun with marketing and left out a lot of the important groundwork.