Who Will go down First: Facebook vs. Twitter

What will be the first to "leave" the Social Media world: Facebook or Twitter?  Both have millions of people on their social networks, Facebook having the larger population, but my prediction is that if anything bad happens to any of these social networks, Facebook will go down before Twitter. The reason I say this is because Twitter.com has a relatively "steady" stream of people on it but Facebook though more powerful and bigger in population is changing. It is really easy to see why networks that were the "biggest" in there time (e.g MySpace) just...Die. Sometimes bigger is not always better! Let me know what you think in the comments.