I think you should also consider the type of users you're targetting on FB and reddit as well. From my experience, I would've assumed that redditors would be le

I think you should also consider the type of users you're targetting on FB and reddit as well. From my experience, I would've assumed that redditors would be less likely to sign up because they're already at a place (say the hiphopheads subreddit) to browse and read stuff related to hiphop, so I'd think it's less likely for them to go on to another site to read similar content. Where as on facebook it's users who are just browsing facebook and there isn't any hiphop pages for them to read on FB so if they click through, they can continue reading more about hiphop.