9-8-10: Just rec'd a PDF of this review article entitled, "Active video games to promote physical activity in children and youth", by Elaine Biddis and Jennifer Irwin. It came out in the Archives of Pediatric and Adolescence Medicine, 2010; 164(7):664-672.
The objective of this study was to "...systematically review levels of metabolic expenditure and changes in activity pattenrs associated wtih active video game (AVG) play in children and to provide directions for future research efforts." This covered published studies spanning Jan. 1, 1998 to Jan. 1, 2010.
If you'd like a copy of this study via PDF, send me an e-mail at firstname.lastname@example.org.