Anyhow, although that implementation is in Second Life, I'm by no means committed to that particular virtual world. As such, I'm very excited about several upcoming virtual world products:
Blue Mars
Vast Park
The former is a game world (an entire, empty "planet" on which you can construct large cities), while the latter is an open source development platform. The extent to which I'll be able to incorporate these in my research remains an open question, but I'll be looking forward to trying.