Apple and Google are interesting comparisons. Some significant part of Apple's success lies in becoming identified with "cool": its products are stylish and fashionable in addition to being useful. Google's success, on the other hand, rests very little on that; it started out as pure utility (search), something people used not because they had lots of friends using it or because it was "cool" to use it, but because they tried it and it got them the results they wanted. And even if Google has become known recently as something of a "cool" company, I don't think that its individual products are identified as "cool" in the same way Apple's are.

So it may be worth asking: is Facebook more like Google, or more like Apple? Or in other words: would Facebook survive a demotion from "cool, trendy place to be" to "utility?" Is such a "demotion" happening as we speak?