I go NamastePlatypus's route, more or less.
I usually send off an email with a list of books that I liked (my friends know I'm wonky and weird that way

) - I have them broken into 'general,' 'pregnancy,' 'baby,' and 'breastfeeding' categories. I offer that we cloth-diapered, and if they are considering it, I loved it and would answer any questions they have. And I also put a couple links (I think the Oknocirc.blogspot one), and say that they should research circumcision, that it's something that I never thought much about until we asked our Pediatrician about it, and she told us that the AAP no longer recommends it, and that she doesn't do it unless the parents have a religious reason. (Since we have dds, I can't offer any 'parenting an intact kid' experience to them) --- And I add that I would have wanted someone to share these links with me while I was pregnant with dd1, so I am sharing them now.
...And then I pretty much leave it alone. Ironically, since I started including the circumcision information, my friends/family have *all* had baby girls.

But at least I've shared the information. I have had several friends that I've shared the email with, thank me later for the book recommendations etc. So hopefully it's getting the word out.
I also occasionally have posted a circ-related article on FB. But I know I'm a FB freak, and not everyone is on often enough to notice a new link (and I post enough stuff that it would be easy for someone to ignore or miss it). So I do send the email too.