I've been a green tea drinker for years off and on (am on right now) and find that I feel a lot better when I'm having 3-4 cups a day. My skin also looks better. That being said, I really don't buy into the idea of green tea itself being a fat burner. Here's why: there is irrefutable evidence that green tea is an antioxidant. If green tea were a fat burner, that would mean it was an oxidant. There are some things that can be one or the other under specific conditions but not both at the same time. I tried to post a link to a wikipedia explanation of this, but I'm not at 25 posts yet
If you google pro-oxidant, it should bring up the wiki entry.
Professor Jay, the guy behind the 9th day diet, has some videos out that explain this in layman's terms.
All of this being said, like I said, I DO drink it myself. I find I eat/snack less when I'm on it and also like the skin benefits I see.