The old behavior amused me. There's probably a decent argument for it, but it's kind of infuriating:

theonemind@onemindsmachine ~> echo $(badfish) fish: $(...) is not supported. In fish, please use '(badfish)'.

echo $(badfish) ^

"I know exactly what you meant. Not gonna do it."

`echo (goodfish)` just looks a lot cleaner to me. and as i am still using other shells some times (can't install fish on all my clients machines) the visual difference between `()` and `$()` helps to make it more obvious which shell i am currently using.

Seems like just printing a warning to stderr or something would be a reasonable behavior (or even just printing to the screen when interactive in some special way that doesn't go to stdout or stderr in order to not mess up scripts)

When they added support for && it really made my life easier with pasting snippets, happy to see this now as well

Also support for the 'export FOO=42' syntax helped a lot, with some care very simple scripts can be made to work both on fish and traditional shells

Nice!

I recently gave up on Fish after 3 years of using it as my primary shell. It was nice, but not nice enough to make up for all the pains of being different from POSIX shells. Glad to see Fish improving on that in a small but concrete way.