As far as I see it, diets are divided to two main groups:

• Calories - this is today's mainstream. Basic idea: eat less calories than your body consumes (negative calories balance) to lose weight. Eat more calories than your body consumes (positive calories balance) to gain weight. There are many diets with this basic rule and it's not really important if you count calories, point meals or something else.
• Others - diets where calories isn't main principle.
  For example: Montignac (see: http://en.wikipedia.org/wiki/Montignac_diet). Another example is blood type diet.

There are also diets that represent some combination of the mentioned two groups (calories with some other principle).

In the mentioned two groups I'd say that I belong to the mainstream (calories count). I can't say that all other system don't or won't work, but from others and mine experience calories count does work.

Important notes:

• I'm not some kind of nutrition expert, even not a dietitian. Therefore you won't find menu plans in my site. What you will find are general tips/principles and common sense.
• A word of caution: many sites, "specialists" and dietitians offer menu plans. In most cases they even don't try to personalize the menu plan and there is no feedback (allergies, preferences, life style and so on) from your side. They just give you a ready plan. Moreover no physical checks are made. It seems to me that taking a blood sample and taking into account some factors (cholesterol levels, vitamins ...) shouldn't be neither hard nor costly. But finding someone that takes into account all these factors is borders with science fiction (this is from my experience). Therefore use common sense and be careful because some diets can harm your health.