I don't disagree, but the definition of "everybody" has gotten bigger and that counts too. AOL may have been the place to be in the 90s, but it was still a sha

I don't disagree, but the definition of "everybody" has gotten bigger and that counts too. AOL may have been the place to be in the 90s, but it was still a sharp subset of my friends and acquaintances that were there, vs. the almost complete set on Facebook. And USENET/dialup/etc were even more selective. It's only been very recently (relatively speaking) that a majority of people were online at all, never mind aligned on a particular site. I think you probably should compare more to something like AOL Instant Messenger, which had much closer to a 1:1 usage ratio of online computer users to software users (at least in the US market). The only real reason they went away was because social networks like Facebook are much more cross-connected and oriented towards group communication. The tagging features are huge, for example, since they potentially engage a lot of people at once. Ditto resharing, etc. So the IM paradigm in general got consumed by larger social media--it wasn't a problem with AOLIM itself. But that sort of obsolescence is a vulnerability of a system that only does one thing. Facebook would probably mutate in the same situation, not die off. The other factor is smartphones: a much larger number of people are online all the time now. If MySpace had their rise in the smartphone era, I'm sure they would have been much harder to displace. The fact that Facebook's opening their doors to the general public corresponded roughly with the release of the iPhone and subsequent rise of the smartphone was a huge bump for them. Upshot is that a vastly larger percentage of a vastly larger number of customers are aligned on Facebook compared to older social media, and Facebook itself, as a platform, is relatively resilient to the changing needs of the customer. In an industry where both the customer acquisition and customer retention metric is "how many of your friends use it," I think Facebook will prove to be much harder to displace.