What are the features of elm 0.19? and when is it gonna be released?
The broad strokes are at https://github.com/elm-lang/projects/blob/master/roadmap.md
As far as when: when it’s complete! I know that’s not a very satisfying answer, but it’s not healthy to give a hard date. Evan’s working really hard on making something great, and preparing little status reports with artificial due dates is just going to slow him down. 
Would be nice to see this roadmap updated. For example, https://gist.github.com/evancz/1c5f2cf34939336ecb79b97bb89d9da6 (data interchange) looks like it might getting worked on at the moment?
Anyway, happy to wait.