Always a good question, because to find good content and to get value you need to have a good network. Try some of these links for advice and tips on who and what to follow.
HSJ, The Nursing Times and NHS Employers pick the clinicians, patients and families who are using social media to inspire, campaign spread good practice and raise awareness.
#WeCommunities http://www.wecommunities.org/
Connect, drive and support tweeting communities, see their website for lots of great resources
#WhyWeDoResearch
A campaign to raise awareness of research in the NHS
The Healthcare Hashtag Project http://www.symplur.com/healthcare-hashtags/
Discover Where The Healthcare Conversations Are Taking Place, Discover Who To Follow Within Your Specialty Or Disease, Discover What Healthcare Topics Are Trending In Real-Time
#EBP Sharing Evidence Based Practice on twitter