Have you ever seen the movie, "The Butterfly Effect?"  The basic premise goes along with the old "Back to the Future" movies where one small choice sets life on a totally different path.  For instance, a teenager who drives drunk and kills someone in a car accident has forever impacted both his life and the lives of those who both knew and might have known the person killed.  Our choices have enormous ramifications for our futures, and that's why Paul talked about the things we choose to set our minds on.  Those who choose to fill their minds with things of the flesh will find themselves constantly indulging in the flesh.  I think that's one of the dangers of passively engaging in entertainment.  I'm not about to say that all entertainment is evil and that there's a list of TV shows, movies, and music that followers of Christ need to boycott.  However, it is our responsibility to engage actively in media to critically understand exactly what the artist is trying to communicate.  The things that go into our minds do affect our thoughts, and we have to be diligent at setting our minds on the Spirit rather than on the flesh.  The mind set on the flesh leads to death, but the mind set on the Spirit leads to life and peace (Romans 8:6).