When I heard that the Dynamic Language Runtime was going to be open source, and subsequently heard some things that Miguel said about it I knew it was only a matter of time before DLR support was added to Mono.  It sounds like only 15 days after the announcement of the DLR it's already made its way to Mono.  As M. David Peterson points out, it still has a ways to go but it's promosing to see them making such good progress so soon!