Georgia Tech actually has a Robotic Musicianship Group in its Centre for Music Technology, which means that some lucky so-and-so's are getting government funding to form hippie drum circles with an array of artificial companions. In the video above, two robot demonstrate their ability to listen to grooves laid down by living breathing meatbags, and jump in on their own instruments when the mood strikes.
Professor Gil Weinberg explained this "musical Turing Test" to Wired:
The processing allows [the robots]to analyse and improvise. In one of the applications, we use a genetic algorithm...You have a population of something, and then you do mutations to all of these little things—in my case it's musical motifs—mutations and cross-breeding between the musical genes, in our case, and then you have a new population that better fits to the environment.