I came across this two-page article by Jonathan Leavitt and Nicholas Christenfeld (University of California, San Diego). The article published in Psychological Science is an experiment that examined how spoilers might affect readers`enjoyment of novels. I thought how it would relate to videogame narratives and a good thing that Scott Juster over at PopMatters wrote about it. So read his blog post and comment.
Leavitt, J. D., & Christenfeld, N. J. (2011). Story spoilers don’t spoil stories. Psychological science . URL http://dx.doi.org/10.1177/0956797611417007