[tim333]

Though this study is better it still doesn't really seem to distinguish cause and effect. ie is it

- your real social life sucks so you spend time on facebook, or

- facebook causes your life to suck?

From personal experience I find more the first one. You could try an experiment where you persuade participants to be chosen at random to either spend much longer on facebook or much less so the change would just be facebook usage rather than other life factors?