i like the like button. Share? No. Not if it shares with the sites like FB. A couple of things I hope for.

I know this is your site and it's not up to the community per se but can you put up for a vote on the share idea? Just so you can get an idea of who really would like this? I know for me, I belong to FB and use it but I'm very impersonal on FB, this stuff is far to personal to share openly like that. Secondly, is it only your own posts that would be shared? i think that's the only reasonable and acceptable way to do it.. And lastly, I think an opt out button would be good if you go through with this so that those that never want their replies or posts shared at all, cna turn it off on their profile. If i remain in control of whether certain posts or all of my posts get shared, I have no problem with it. I don't know if I'm helping but just some ideas..