Prezi's engineering team writes about Elm, using multiple programming languages, bug bounty handling, and infrastructure costs.
HN links it for Prezi's early backing of the Elm language, its response to a bug bounty report, and its polyglot engineering approach.
The project is supported by Prezi with the aim of making it production ready ( http://engineering.prezi.com/blog/2013/05/21/elm-at-prezi/ ) and all development effort is focused on that.
With the two most recent releases ( http://elm-lang.org/blog/announce/0.11.elm and http://elm-lang.org/blog/announce/0.12.elm ) it is really easy to drop an Elm component into an existing JS application, which we are experimenting with both at Prezi and in the general Elm community.
So I'd (biasedly) say to give it a try. Even if it's still too young for you, I think you'll come out of it writing way better JS :)
If this style of programming interests you check out Elm [1], a functional language made for the web that uses this FRP style. The creator was recently hired by Prezi to work on Elm full time [2].
[1]: http://elm-lang.org/
[2]: http://engineering.prezi.com/blog/2013/05/21/elm-at-prezi/
Here's the response from Prezi http://engineering.prezi.com/blog/2013/12/03/a-bug-in-the-bugbounty/
http://engineering.prezi.com/blog/2014/01/20/prezi-the-land-of-the-polyglots/