Though I saw no direct mention of this in any of the writeups thus far (they are just announcing it now at GOTO), it appears you can download code for the the VM, compiler, etc from here:

https://code.google.com/p/dart/

(Look in the bleeding_edge branch)

Currently doing a repo pull here so I haven't had much time to look around at it yet. I'm cautiously optimistic though, it looks quite a bit like I was hoping Dart would look (a bit of the ECMA4/ActionScript feel on top of JavaScript).

See http://blog.chromium.org/

There's a compiler that translates to JavaScript, and a standalone VM.