Nasvhille-based Medicare plan HealthSpring has become the first major Medicare Advantage plan to establish a presence on social media site Facebook, according to a release. HealthSpring said it will use Facebook to establish a branding presence and provide visitors with basic information about the company. The site features video clips and photos from the company's current advertising campaign and directs visitors to HealthSpring's Web site or phone lines for more information. Establishing a Facebook presence required approval through the Centers for Medicare and Medicaid Services, the company said in the release.