There's a trend in Facebook that I find somewhat disturbing. People post movies on their walls or send movies to you and encourage you to click the movie. When you do, the first thing you see is a message that sayss "You must share/like this before seeing it." This begs the question: What, exactly, am I sharing? What, exactly, am I liking?
Maybe somebody can light my candle, here, but I don't understand why you would need to force people to share things or commit to saying they like it, if they haven't seen it yet. My first reaction—well, my only reaction, really—is to ignore such movies, even if the title is enticing. So if the idea is to get more people talking about it, or sharing it, isn't that a counter productive approach? Let people view the movie and let them decide after the fact whether it's worth sharing or not. Otherwise, the message you are really sending is "Send this along before you realize that it's really not that good."