Three dimensional virtual worlds (3DVW) have experienced a large growth in number of users, and are being used for collaboration activities. In parallel, the research field of Computer Supported Cooperative Work (CSCW) has developed taxonomies to classify systems that support collaboration. However, the CSCW perspective presents a bias towards traditional user interface paradigms, whose affordances are quite distinct from those of 3DVW, which include features such as the spatial environment, embodiment, and their dynamics. These are features which are regarded as significant factors in the research field of Presence, and yet, in our opinion, are not well appreciated from the perspective of CSCW analysis. Because of this, we question of the ability of CSCW taxonomies to properly describe the collaboration characteristics of 3DVW. By "properly", we mean to say that 3DVW bring to fore collaboration characteristics that are in fact distinctive of them as collaboration tools, impacting collaboration in ways that are seldom found in usual groupware, and yet CSCW taxonomies do not distinguish them. We posit that these features should be contemplated in CSCW taxonomies and their usefulness taken into account in the development of future systems that aim to support collaboration.