What about the case where it isn't a long-form post, but something more casual like a retweet or a link to some website? I can see the blog solution working out there, too (cf. Daring Fireball), but you might not want to have that full setup for more ephemeral (yet interesting) stuff. There also might not be one specific topic. I'm not disagreeing with you, I just wonder if there is a way to use a social network like Google+ for Everyone, as they market it, which is sensible. Maybe not.