I think Facebook is heading for the same kind of "irrelevance" as Microsoft or IBM.
Which is to say that they are irrelevant to a lot of people, particularly "early adopters", but they'll be around and profitable for a long time.
Which is to say that they are irrelevant to a lot of people, particularly "early adopters", but they'll be around and profitable for a long time.
Similarly, IBM was computers for 30 years.
Comparing them to simply the most popular social website for the past 10 years is not really fair. The fact that Facebooks value approaches those other two companies only shows how insane the current bubble is.
I could easily see facebook surviving long into the future in a similar way to IBM -- with a focus that is shifted from what made them big player, but still doing valuable work (and making money) in the tech "sphere".