从2009年下半年起，新浪微博开始进行内测，在短短不到一年的时间里，便成为了诸多社会舆论公众事件的起源地。微博表现出强大的聚合民意、形成舆论的革新力。本文将在全面系统、细致多维地分析微博进行信息传播的特点和功能的理论基础上，以“宜黄强拆”事件为案例，结合传播学和舆论学的经典理论，进行深入地实证研究。微博产生的具有新特质的公众舆论主体 “公民记者”发动了网络“自下而上”的社会“议程设置”,通过实时的信息发布与获取、“意见领袖”的催化，在网络中聚合强大的民意和行动力，推动舆论事件的发展。本文由此归纳分析出微博信息传播营造意见气候、形成舆论事件的几个要件，并尝试总结出其内部规律性的机制。正是这些形成要件和机制让微博呈现出革命性的强大舆论传播力，而这种传播力利弊兼有，如何超利避害，最大程度发挥微博的社会功用，也是本文试图探讨并呼吁进行进一步思考与研究的议题。

From the second half of 2009, Sina microblogging became the public event origin of many social public opinion in less than a year. Microblogging shows innovation force of strong aggregation and the formation of public opinion. This paper will be a comprehensive and: systematic, detailed multi-dimensional analysis of the features and functions of microblogging, with "Yi Huang Demolitions" as a case study, combined with communication and public opinion of the classical theory, and conduct in-depth empirical research. Microblogging produces the public opinion with new subject -"citizen journalists" to launch a network of "bottom up" social "agenda setting", and aggregate public opinion and action strong in the network to promote the development of public events, by real-time information dissemination and access and "opinion leaders" as a catalyst. This paper summarized and analyzed the essential elements of building opinion climate and forming the public events in microblogging, and try to summarize several elements from its internal regularity mechanism. It is the essential elements and the mechanism for microblogging that presents a powerful mass media in the revolutionary force, and it has both advantages and disadvantages, so how to profit and avoid is also what this paper tries to discuss and call for further thinking and research issues.