Finally, I have drafted the first version of the topic of my PH.D. thesis:

“Evaluation of the Acceptance of Virtual Worlds in the Tourism Sector: An Extended Technology Acceptance Modelling Approach”

Abstract:
This research makes an attempt to investigate the acceptance of virtual worlds as one of the new information and communication technologies (ICT) emerging from the current development of the World Wide Web. The goal of this doctoral study is to evaluate the acceptance level of various target segments with respect to a specific virtual world and to identify those virtual world dimensions that are mainly responsible for the acceptance of virtual worlds by its potential users (e.g. tourists). Therefore, an evaluation instrument will be developed based on literature research and complemented by qualitative expert interviews that will then be employed by adopting an extended technology acceptance model (TAM).

If anyone has any comments or input for me please feel free to contact me. Thanks!