The special E3 presentation demo I was able to play was on the X-Box console at the Microsoft booth. There were two stipulations to the special demo. Stipulation 1 and best for me was that my character couldn't die so I could play through the whole demo without worry of having to restart, this won't be the same factor for the game's release. Secondly, the storyline and locals may not be in the released version of the game so don't worry about reading spoilers.