they understand that social media has value for their companies, observes John Bell on the Digital Influence Mapping Project blog. But Bell also cites findings showing that social spending accounts for less than 1% of an average marketing budget. What marketers may be missing is that social media, once just an experiment, is now experiencing an imperative to leverage and interpret best-practice customer engagement. What's an optimal social slice of the marketing budget? Bell says companies should point to a three-year goal of 18% of total marcom expenditures.