I believe musicXML is useful in providing a common format that can be imported to and exported from a good number of music programs (see http://www.musicxml.org/xml.html) and that it can represent complex scores but I think it's OTT for the dt. See http://www.musicxml.org/xml/helloworld.htmlfor their "hello world" example.

Technically, I think Songwrite is adequate for the dt. The problem with it is that it is an obsolete proprietary format. The closest match to what is done in Songwrite in the dt I know of that is current and supported is abc.