Taking the news practice of “Boston Bombing” reporting in the America in April 15th into a case study, this thesis elaborates an innovative concept “micro-media” which features mobility, social interaction and citizenship, and argues how this new form of media ecology poses critical challenges for professional news agencies in breaking news reporting in both the spatial and temporal dimensions. Roles employed by western media agencies to adapt to this “we-media” 24/7 news cycle environment can be categorized into “Gate-keeper”, “Gate-watcher” and “News- curator”. As a constructive insight yet theoretically soundless approach, ”news curator” strategy requires logical convergence, context and details in practice, and necessitates “appropriate silence” and “pragmatic philosophy” in ethics to guarantee journalistic professionalism.