I'm still waiting for a mature product that I can be confident about sharing with them - G+ is there, but not really anything else. I don't want to get +20 people onto a site only to have it go "sorry, we're shutting down", or "yay, we've been acquired, sorry early adopters" in a year.
I've been burnt before, and I hate it when it happens.
Otherwise, how is the service going to survive? They have to monetize somehow down the road to pay the bills.
See if you agree with what the creator of Pinboard says: http://blog.pinboard.in/2011/12/don_t_be_a_free_user/
I personally run a site called Handpick that helps people curate links and inform in a considerate manner:
I have paying subscribers who help me keep the lights on and do not have pressure to monetize my users' data in any way.
The question is: do you care enough how your data is handled to pay for the service?
RFC 3 is older (by a few months) than me - April 1969.
Bob Kahn and Vint Cerf are about 70. (That's old enough to be a great grand-parent.) Jon Postel was born in 1943. There are many old women who are Internet pioneers because they were librarians, and the Internet was something that got rolled out to university libraries early on.
I could see them picking up on something like this if they could overcome the trust barrier. Most 50+s I know don't trust Facebook and don't have an account there (I don't trust them either, but I'm in the minority in my age group).