However automated composition is something that a lot of people have experimented with before. So far there is nothing that works really well.
Emily Howell?
I know the conversation here has run its course, but I just wanted to add: whether or not Emily Howell is seen as something that "works really well" as an automated system is probably up for debate. It seems to require quite a bit of input from Cope himself in order to come up with sensible, interesting music. For example, one of the most popular pieces from Emily Howell is this fugue: https://www.youtube.com/watch?v=jLR-_c_uCwI - we really don't know how much influence Cope had in creating this piece of music, because the process of composition was not transparent at all.
There have been a couple of brief discussions of this in the Open Thread, but it seems likely to generate more so here's a place for it.
The original paper in Nature about AlphaGo.
Google Asia Pacific blog, where results will be posted. DeepMind's YouTube channel, where the games are being live-streamed.
Discussion on Hacker News after AlphaGo's win of the first game.