Stop fragmenting languages, we don't need another one except if it's revolutionary.
There's some very good principles like the fact that it can compile to many languages but like CoffeeScript I just don't see the point. Want to do some c++ why not using it? Want to do some JavaScript? Then use JavaScript.
There is just too much on the table when it comes to language compilation, I mean if the compiler itself has a problem with your code? It's a bug between what you built and its runtime: what can you do about it? A client is waiting for you, you've got no time to lose contacting the compiler's developers, you're just fucked. Don't get me wrong, I like to play with these languages but that is what they are: toys.
The hard reality is that browsers only support n amount of languages and we are stuck using them.