What are "open, cheerful intentions"?
Open? Dart has been open-sourced for 2 years now - only having its proof-of-concept done in-house before the announcement.
Cheerful? Not sure how one language that compiles to JS is more "cheerful" than an other, but we're really a cheerful bunch in person. I'm sure you could have a beer with us if you'd like :)
As to the your and the OP's point about Dart being another CoffeeScript, this is really far from reality. CoffeeScript is just syntax changes, and that's not sufficient for fixing JavaScript major problems - which come form its semantics, not it's syntax.
Dart and CoffeeScript are actually quite far apart on the spectrum of compile-to-JS languages: Dart tries to keep a similar syntax and fix the semantics, CoffeeScript tries to keep the semantics and "fix" the syntax (I personally find CoffeeScript very hard to read). Claiming that Dart is another CoffeeScript, to me, shows a real lack of knowledge about one or both of the languages.