The BodyTrace is a wireless scale that sends your weight to the Internet. It will be available in November for $119 and it costs $19.99 for a three month weight loss subscription. This is a great way for people to monitor their weight and I can see a great tie in with the food you ate that day, how much you worked out, etc, etc, etc.
However, this is a perfect example of a good idea with a bad business model. I suspect very few will pay 19.99 for a 3 month subscription or 19.99 for an annual subscription for that matter.
In today's world, I really would have expected a Freemium business model (Free + Premium), An Iphone app at Launch (because everyone will ask) and some tie ins with value added weight loss programs / products / services.