Ok, I haven't lost 200 pounds, but I have lost 105 (and have about 15 to go). But since there aren't many around that have lost 200, I thought I would chime in.
First, fat loss and skin shrinking up don't go at the same speed. Well, they can, but you can lose fat a lot faster than skin can shrink up, so if you lose 2 pounds a week initially, and then later 1 lbs a week, you will be dealing with some loose skin somewhat (most likely), but it could shrink up later.
What I'm finding is that for the most part, the skin is shrinking more than I thought it would and I kind of had worst case scenario in my head as I have REALLLLLY bad skin - I get stretch marks easily. I get scars easily, etc.
Do I have loose skin? Yes. But it's also still shrinking up, so I don't know how much really loose skin there will be in the end. The worst of it is my tummy and my underarms - though I have it everywhere, it's just more noticeable there. My tummy I think is even worse because of tons and tons and tons of stretch marks from pregnancy. My underarms have been a problem for me since puberty - all women in my family have big arms and now I have bat wings.
But even on my bad tummy, I don't have a flap of loose skin. It's baggy and wrinkly and loose, but not enough to create a flap of skin that will be hard to keep clean and dry. And, it's still shrinking up. Just last month my arms shrank over an inch and I am certain ALL of it was from loose skin shrinking up (finally).
And really, even with loose skin, you still look and feel SO MUCH BETTER than before. My husband thinks I'm beautiful. He said a couple days ago, "Let me turn this light on so I can see my beautiful wife" And he is NOT one to say things he doesn't mean.
Now, with all this said, I do think it helps to eat a good diet and to exercise. Treating your body right will help with it being able to respond in a healthy way too.
But really - once you really get going, you'll worry and care about that loose skin less and less.
I'm aiming for healthy and fit - not perfection.