As far as I can tell, the difference is that one is a Group and one is a Fan Page. The Group was started by friend of SCAA (and friend of mine) Nick Cho before Facebook introduced Fan Pages. A lot of businesses/non profits have made the transition from Group to Fan Page but for SCAA I think it is okay that both endure. I will double check with Tara Shenson, SCAA's resident social media go-to-person to ensure that is intentional and return with any relevant updates. Thanks!
All the best,
SCAA Professional Development Director
WBC Board of Directors