LANSING, Mich., June 3—Pure Michigan‘s digital marketing efforts continue to push the travel agency to the forefront of marketing success. Pure Michigan Facebook fans doubled in count since January 2010 - as of May 31, 2010 the number of Facebook fans has risen to 50,000, continuing to make the Great Lakes State one of the nation’s tourism leaders on the social media outlet. Additionally, Pure Michigan now has over 5,000 followers at @PureMichigan on Twitter. On both Facebook and Twitter, fans find up-to-date....