Communities of practice have traditionally supported learning and knowledge exchange within a professional field. However, little work to date has examined how individuals use social network functionality for professional development in these types of communities. We present a qualitative investigation into how the social transparency provided by SNS functionality influences two important components of professional activity: social learning and professional identity development. We focus on activity within Dribbble, a social media enabled community of practice for graphic designers. Through a series of interviews with novice and experienced Dribbble users who work within and outside of traditional organizations, we identified ways they leverage social media features for learning and skill development. We find that benefits of the site are dependent on extensive social capital development activities in order to garner attention for posted work. Our results inform the design of online social settings for professional development.