The GameFlow model strives to be a general model of player enjoyment, applicable to all game genres and platforms. Derived from a general set of heuristics for creating enjoyable player experiences, the GameFlow model has been widely used in evaluating many types of games, as well as non-game applications. Initial applications of the GameFlow model were limited to real-time strategy games. However, in order to be considered a general model of player enjoyment in games, the GameFlow model needs to be applied to a more varied set of play experiences. In this article, we revisit the design of the GameFlow model, review the various applications and derivative models, and discuss on-going analysis of the model. Subsequently, we describe a study that aims to extend the initial validation of the GameFlow model to incorporate additional game types. We report the results of expert reviews conducted using the GameFlow criteria to evaluate first person shooter games on Sony PlayStation 3 and adventure games on Apple iPhone. Our findings provide insight into the manifestation of the GameFlow elements in these types of games and also highlight some of the genre-specific considerations in the application of the GameFlow model. Key issues are raised and discussed in relation to immersion, social interaction, and multiplayer games.