I've said some harsh things about Weight Watchers (examples here and here). But let me be honest: I've also learned a lot from Weight Watchers. Not necessarily about nutrition, as I will not be eating low fat again any time soon, but about other aspects of weight loss.
WW celebrates non-scale victories, or NSVs. So you didn't lose weight, but your wedding band fits better. Or you are losing inches, or you are moving more. They invested a lot of time in framing success to include things other than the scales. Now that the low carb diet is stalling for me, I am celebrating a lot of NSVs.
WW celebrates significant milestones, such as a loss of 10% of your body weight, 25 pounds, 50 pounds, 75 pounds, 100 pounds... Achieving these milestones is very difficult, and they are appropriately recognized. I have celebrated on my previous blog my first 10% goal and 50 pound weight loss.
WW provided a "safe" environment, in which everyone can feel comfortable sharing weight loss successes and failures. I think the search for a "safe" environment may be one of the reasons why a lot of low carbers seek out others on the Internet. As a former Weight Watchers leader, I know the weekly pep sessions were very helpful. It's simply people helping other people to succeed.
WW helps prepare for upcoming food events (e.g., Halloween, Thanksgiving, Christmas) by mental rehearsing, anchoring, empowering beliefs, and other psychological tricks. Since Gary Taubes claimed in Why We Get Fat that obesity has been reframed as an eating disorder, or a psychological proglem, the low carb community tends to avoid psychological tricks. Personally, I find them useful, as weight loss is, for me at least, first and foremost psychological. I have to get my head "in the game," so to speak. Willpower, as I mentioned before, is a crucial low carb success factor. And ultimately, willpower is psychological. Weight Watchers helped a lot in the willpower department.
So even though I do not agree with their weight loss program or share their nutritional beliefs, I am taking the useful things I learned from Weight Watchers and applying them to my low carb lifestyle.