Weight Watchers assigns points based on ingredients and amounts. This just uses straight up calories. Difficulty with Weight Watchers is it takes time to do data entry, and you cannot always accurately put it in because of complexity or incomplete database. With this, you still won't know how much calories something from a restaurant contains but every time you make your own food you can see the package. Except on fresh food such as vegetables and fruits you prepare yourself.

Yup, even the weekly total is very similar to the Weight Watchers system.

These kind of weight loss programs can be useful, but only if you are also committing to change the way you eat for the long term.