'Facebook fatigue' kicks in as people tire of social networks | The Register

Walled gardens have a long history in the online world, dating back to Quantum on the C64.  They always have the save effect:  rapid build up as people attract their friends then slow deflation as people move on to something else.

Now it looks like Facebook is starting to experience the same effect.

Social network-like technologies will certainly change the way we communicate in the future, but it will not be through walled gardens like Facebook.  That model is simply not sustainable; to keep everyone in your garden, you are competing with the entire Internet.  Not a good long term prospect if you ask me.