On the weight watchers thing - even though i am not very experienced in the diet dept. i have recently gotten two of my friends of the plans :p
Mainly because they were simply not eating enough. From one of the girls plans, she was taking in around 1000 calories a day, around 800 short of her recommended for weight loss.
The other friend is a gymnast, and since starting uni she has gone from a UK size 8 to a UK size 12...which is a big jump according to my gf lol. She has just started weight watchers, and after taking one look at the plan denounced it lol. It split the meal intakes over 3 meals, brekkie, lunch and dinner, and didnt include enough carbs or fats...
Being a gymnast, if she had stayed on that plan, she would have lost a great deal of muscle which would comporomise her sport, so i persuaded both my friends to have a look at the calorie calculators. Neitehr seemed to grasp the concept of losing body fat as opposed to weight.
The problem with cutting calories down completely is that you go into survival mode etc. Anyway,
have a gander at this page here if you haven't already, its been a great help to me! For all i know however this particualr weight watchers plan could be fine. I am a cynic when it comes to things like these however, especially after hanging out here for a month! Like cpl said, let us know some more info and the experts (not me lol) can take over!