Just another language which compiles to Javascript.
Till now with their own virtual machine.
But already without their own Editor.
And, as always, without any programming language roadmap.
https://github.com/dart-lang/sdk/issues/5454 https://github.com/dart-lang/sdk/issues/18929
https://github.com/dart-lang/dart_enhancement_proposals
They send out regular notes about DEP meetings, which proposals are under consideration, and which have been accepted.