Communication in highly interactive distributed applications, such as massive multiplayer online games, can often be performed efficiently using multicast, i.e., application level multicast. However, in applications with a very dynamic group management, the multicast tree will have frequent changes, and in applications that have stringent latency requirement, this operation needs to be fast. Current multicast approaches either have no notion of reconfiguration, they do not care about tree reconstruction latency or wrongly assume that this is a fast, atomic operation. In this paper, we have focused on dynamic reconfiguration and have tested different ways for a node to join a tree. Our results show that this is an important issue for the class of highly interactive distributed applications.