The modern social and cultural trend is that users themselves produce knowledge, participate in it, and share the knowledge. Under this circumstance, a new technology of visualizing information to help users have access to the knowledge easily and fast is attracting the industry's interest. The emergence of web 2.0 contents and social network service are good examples of such trend. In this paper, we examined the type of linkography visualization in the web 2.0 contents from various viewpoints. We first focus on the theoretical aspects of various information visualization methods within web 2.0 type interface. Then, we give a deeper analysis of various visualization types and their utilities based on tag clouds and visual search method.