The first functionality update that arose out of the Goldsmiths symposium last weekend was a fix to the way MIDI velocities are handled. As of the latest svn-latest check-in (2 mins ago) when you call midi-play, event velocities will reflect the last dynamic seen in any given part (rather than retaining their default velocity). Also, if you have hairpins (crescendo/diminuendo marks), then the notes that are under these will have correspondingly increasing/decreasing amplitudes.