Going viral is social media's ultimate measure of success. Viral means more than just popular: Viral means becoming outrageously, over-the-top popular by virtue of being passed around by social media's most promiscuous retweeters and sharers. If you are one of the 10 bazillion social media marketers out there trying to figure out how to cook up something viral for your client, perhaps the "Understanding Viral Content Marketing" infographic from Mashable will help.