You’ve read all of your free items this month. To register, get added benefits and unlimited access to articles, Become a Member. Already a Member? Sign in. Advertising Age Article Abstract Package-Goods Players Warm Up Slowly to the Social-Media Scene Kraft, Coca-Cola, P&G Dip Cautious Toe Into Twitter and Facebook By Emily Bryson York, Published on April 13, 2009 4 Want more Access, Content & Connections? Upgrade to Membership. We are glad you are enjoying Advertising Age. To get uninterrupted access and additional benefits, become a member today. Become a Member Already a member? Log in.