I posted a comment on a blog yesterday.  Today, it was approved.  But they went a step farther.  At the bottom of my comment they add a line stating D has posted.... and they gave the full title to one of my posts that was fully hyperlinked.

Usually, I get the comments merely approved.  I don't see the advantage to this site giving me back an extra link that has a different keyword phrase than the one I was going for with my comment.

I'm enjoying it.  But can someone tell me what's with the altruism?  Is it pure? If not, what's their advantage?