I think some of you already know the answer to this, but I thought I'd post a link for you:

http://health.yahoo.com/experts/spor...e-for-fitness/

"Researchers at the University of Wisconsin, La Crosse, focused on quantifying DDR's potential physical benefits and determined that it is comparable to many other aerobic activities and could result in significant weight loss if used regularly.

All subjects showed a significant increase in exercise intensity as they participated, with adults burning more overall calories than kids (based primarily on expected differences in body weight).

How much exercise did they actually get? According to ACE, the participants burned: 5.9 kcal/min on light mode (comparable to an easy walk on a treadmill), 6.7 kcal/min on standard mode (equivalent to riding a bike about 12 to 14 miles and hour) and 8.1 kcal/min on difficult mode (similar to the benefits obtained with high-impact aerobics). They used the Sony PlayStation version of the game for this particular study."