Jamie, I have used WATP as my main source of cardio since I've started and I've lost 151 lbs.
But even more importantly than exercise is your food plan. If your calorie intake is more than your calories expended, you still won't lose weight. What is your food plan like? Oh wait, I see you've lost 3 lbs in 3 weeks. That's a good start, particularly if you don't have a lot to lose. There is also a WATP monthly thread with lots of other successful losers.