How does it work?

I can't give too many details otherwise people wouldn't have to sign up to the SW website and then I could get in big trouble.

Basically there are lists of foods you can eat.  There is a free foods list that includes fruits, veggies, and meats which you can eat as much of as you want.  Seriously, no measuring or weighing, you just eat until you are satisfied.  Then there is the healthy extras list which consists of dairy products as well as high fiber choices  of stuff like cereals or breads and some soups and snacks.  You should have 2 measured dairy products and 1 fiber choice a day.  They want you to eat your 5 fruits and veggies.  The last list is your syns.  I can have 10 syns a day.  A syn is anything that is not on the list and allows you to splurge on the really yummy stuff like your sweets, chips, cakes, higher fat foods, etc.  This is all called food optimizing and it is supposed to work really well.