Green tea is something you should include in your diet just for it's overall health value. But in addition to that, it has also been shown to help your metabolism. If you're looking to burn fat and lose weight, a fast metabolism is of great help. Green tea is so good of a metabolism booster that if you look at the ingredient list in most fat burners, green tea is usually high on the list.
I personally don't like the flavor too much, so this is my little secret to getting in green tea. I get a gallon of water, I mix in some crystal light and pop in about 10 tea bags of green tea. I let it brew overnight and then I start drinking it whenever I feel like having a green tea boost. I notice that I get a little pick me up, I'm not sure if it's the caffeine, the effect of green tea, or both combined. Either way, it's a good substitute for when you don't feel like having coffee and as research has shown, it will give a boost to your metabolism.