I am working with the Beaumont Weight Control center in the Detroit area. They are very thorough, and the best thing they did for me was give me a pedometer, and tell me to shoot for 10,000 steps per day. This way each morning I take a quick note on my palm pilot of my morning weight and the number of steps from yesterday. I've been tracking it on a spreadsheet, and while I have been pretty faithful to the initial diet (I'm not banded or on pre-op liquids yet) I can definitely see from the trends that days of high exercise lead to big drops in weight, while days with lower activity result in minimal weight loss. I think my body is very clever at trying to maintain or increase my weight, even when the calorie count has dropped. Adding exercise helps keep the metabolism up and lets the pounds come off.
So I heartily recommend getting a pedometer. You'll be able to see how a normal inactive day only results in a couple thousand steps, yet mowing the lawn, or vacuming the house gives you a couple thousand boost. I like to ride my bike, and I clip the pedometer on my shoe, since it doesn't register anything if it is on my hip. If you shoot for having a few 10,000 step days per week, with most days over 5,000, you may see some improved weight loss.