young = time but no money
older = more(ish) money and less time.
i still see facebook as something people fool around with in their dormrooms, a kindof tv/DVD kind of thing - if you want to sell to this demographic, sure facebook is king. i just don't see any utility to it for the older set (who incidently, are not without disposable income of their own...)
"Old age and treachery will overcome youth and skill."