Henry Jenkins, fandom and videogames

This video is a very quick and dirty introduction to Henry Jenkins, his theory of fandom, and how we can apply it to the videogame industry, It goes over several of his pivotal concepts, such as textual poaching, audience/producer convergence, fan labour and participatory culture.
It also makes reference to the post 'Videogames 9 - fandom and active audience theory' on the A-level media studies blog at lr-media.blogspot.com.
Jenkins is great, as he is so resolutely positive about fandom, and the ability that it provides audiences to interact with and to create communities around their favorite media products. One aspect of this I didn't go in to is that there is some disagreement about the emancipatory qualities of fandom in general. Are fans truly creating new worlds from the media product, or is it just another example of a negotiated reading (Hall)?