This paper discusses the use of conversational or dialogue games as a basis for building dialogue systems. We give a tutorial overview of some recent attempts to relate the notion of a dialogue act to changes of information state of the participants in a dialogue. These attempts all distinguish some notion of grounded or common propositions. We raise the question as to whether these attempts might make the notion of dialogue game redundant, reducing it to an epiphenomenon arising out of the manipulation of information states. The answer to the question is no, not quite, yet.