I've seen a number of new SGs turn pink over the last month or two. Many of them are very active on the site, I'll see their posts and comments every time I log on, and they try to help others reach their goals too, but there have been a few that... let's just say they haven't put in the work.
One in particular that comes to mind had a profile picture up for a month or two, finally posted a "hello" blog of about three sentences, and then when their set hit MR three days later was pink by week's end. Finally, a month after was a short thank you post and nothing since. No comments on others sets or any groups were listed on her page. Just completely inactive...
There are also several sets that I've seen bought with fewer than 1000 likes or comments. Makes me wonder why someone with over 1500 likes and nearly 700 comments hasn't had her set bought yet...