It's pretty funny, and definitely has the geek factor going for it, but that's not a mind-boggling set of figures.  I dropped about 25 pounds in the same amount of time doing the Couch to 5k.  Granted, it wasn't nearly as much fun as exercising while playing World of Warcraft, but if you're willing to do moderate cardio for a few months, you can do a lot to change your health for the better.  Hell, not just my weight... my heart rate's down into the low 70's.

Of course, you have to commit to continuing to do it... you have to make a lifestyle change, or the weight comes right back.  But once you get the results, it's not that hard to stay committed.