Read below about how Google is getting stricter for those who have purchased or acquired spammy links for their website. They are becoming less tolerant in a gradual responsible way. We just don’t know when they will stop which is the scary thing so those who didn’t get caught initially by “Goog-Fu-Panda” are at risk in the coming cycle of Panda updates.
Study Finds Google’s Penguin Update Getting Stricter Over Time: