Str82u - 5:15 pm on Apr 25, 2013 (gmt 0)
Signups isn't something we're actively trying to garner but when we "socialize" we get flooded on both the site and other social channels. The best bit of advice I've gotten that works for us in social media is the "4 in 5 ratio": post 4 items of interest to your followers/fans and one that promotes the site. Going a bit further than that, we actually only post links to ourselves once a week or less now; the site and any linked social profiles get more traffic from posting news, ideas and conversation than trying to promote a new article or feature. It's free and enjoyable.