Quick: what business Top 10 list contains such strange bedfellows as Starbucks, Disney, Walmart, General Electric and Louis Vuitton? I'll bet you didn't guess Pinterest. Since it introduced Pinterest for Business just last November, the three-year-old pinboard photosharing website has been on fire. And if you haven't yet heard of Pinterest for Business and the company's new set of tools and terms designed to help brands use the site to engage users, you'd better catch up fast. Already diverse businesses including consumer brands, designers, bloggers, retailers, online merchants, publications, non-profits and local businesses have already jumped on the 'PforB' bandwagon.