What will Facebook be to us to in 10 years?

It's an interesting question, and one that as brought up last night at a dinner I was having with one of my older family friends. He said "10 years ago, things like Facebook and LinkedIn didn't exist and 10 years from now, they will likely be dominated by something new".

It struck me hard mostly because as a 21 year old, Facebook and LinkedIn (among others of course) are our primary ways of connecting online. But older people have seen things come and go for far longer, so is this really what's going to happen?

The reason why I highlight Facebook is because I really don't think it will disappear that fast, or even be dominated by something else for a long, long time. Twitter can be brought into this discussion as well--both are used by such a diverse population that it seems impossible that something will come and make them irrelevant to society. Just a 21 year olds thoughts, though--interested to hear others'.