Although socially aware opportunistic communication paradigms are considered to have broad potential applications, very little is known about how the dynamic networks evolve and which nodes are more important both in sustaining the network topology and in forwarding or disseminating messages. Through the concept of walk and the adjacent matrix product of static graph theory, this paper extends a measurement, Katz Centrality (KC) that originated from Social Networks Analysis (SNA), to dynamic evolving opportunistic mobile networks. This is done in effort to examine the dissemination capabilities of different mobile nodes. The cornerstone of this method is the dynamics of an opportunistic contact network can be expressed through time-split observations, which result in a sequence of snapshots. By simply multiplying the adjacent matrix of each snapshot along the direction of time, the resulting matrix, in which the spatial and temporal dependency of the network are fully captured, can be obtained, so as to evaluate the relative information dissemination capability of each mobile node. The research uses two typical contact trace datasets for validation and the results show that several mobile nodes with the highest communicability identified by this method are more efficient in information dissemination than others in the whole network and can be chosen as good candidates when some interventions, such as accelerating or suppressing the speed of message dissemination in network, are required to be made on network.