The way I see this going is that everyone who wants to participate will post their goals (no pressure to put a pound loss number; the goal could be anything from "lose 10 pounds" to just "get my heart rate up a certain number of times a week" or even just "increase the distance you can run/bike/swim/ellipitcal/whatever without feeling awful"). After you've posted your goal(s), check in at least once a week with what you've done toward achieving your goal. So since one of my goals is to get to the gym 4x a week, I will post how many times I went, and maybe what I did each day if I can remember. Or another one of my goals is to cut down on soda and up my water intake. So I will include in my weekly update how many sodas I drank each day.
The big idea is to have a shorter, defined period of time (10 weeks) where participants feel increased accountability for exercising or dieting or both to work toward goals at the end. For me, my goal is obviously swim suit season oriented. Nerdy's goal is to up her cardio training level and see a positive change in the way her clothes fit. Hopefully at the end of 10 weeks of work, we will both see some positive results.
Does that work/make sense?