Not a whole lot, conceptually, it seems. The syntax feels very Nemerle-like to me, though, which is nice. Definitely something to play around with, if nothing else.
Having seen early versions of Rust (I work at Mozilla) I can tell you that the syntax is the last thing they're even considering (though that may have changed over the past few months). Seems like Graydon wants to get the guts right first.
That gets back to my question. What are Rust's advantages over Go or D?