No one is tracking pharma's social media presence better than
WhyDotPharma, and the site/blog has done a nice review of which pharma companies are Twittering the most (Amgen, Boehringer, JNJ, Genentech), and how they're doing it. Some companies are using Twitter to establish a presence and get the word out on corporate news and policies, while others are using Twitter to follow and see what's being said about themselves and the industry.