Positive elements in the comments where the acknowledgement that this is a timely topic and that the paper did a good job of explaining what drives the popularity of virtual worlds. The paper was also credited with giving insight into the way virtual worlds might encourage new ways of information transfer and trust building that are lacking in other forms of computer mediated communication. The motivational attributes that are identified in the paper (see my recent presentation in Finland for more on that) offer a good basis for further research.
The biggest problem with the paper is of course that it is a purely intellectual exercise and not a report on new research. In that sense it was considered premature by the reviewers, who would have liked to see some ethnographic evidence of the practices described in the paper. No argument there, but that will be something I will be working on in the coming months.
On the whole, I am encouraged by the comments. I guess a rejection for this particular conference was inevitable because of the lack of empirical evidence I supply.
On a further note, my contribution has been accepted to the workshop on Communities of Practice in Highly Computerized Work Settings, which is organized as part of the 3rd International Conference on Communities and Technologies at Michigan State University. That promises to be an interesting exchange of ideas.