The Journal of Virtual Worlds Research has devoted its latest issue to medical applications of 3D virtual environments. The issue covers topics such as medical training, psychological applications, and how seriously we should take the studies emanating from this field of research. Not surprisingly, most of the discussions in this journal focus on Second Life, as it is by far the biggest virtual environment on the internet.
Link: JVWR Vol 2, No 2: 3D Virtual Worlds for Health and Healthcare
(hat tip: ScienceRoll)