You've got some good pieces, and it looks like you generate some nice speed, but overall there's a bit too much chaos going on for it to be reliable.
I would focus initially on stablizing the axis you're swinging around. There's a lot of back-and-forth movement at the moment that is making it hard for you to get your swing bottoming out in the same place each time. That's where the fats and thins are coming from -- they are two sides of the same coin. When your low point gets behind the golf ball, you are either going to hit the ground first, or your subconscious will try and save the shot by bending your elbows or breaking your left wrist. Now the club's traveling up into the ball and you get tops and thins.
This is what you are doing now (using the driver swing because it exaggerates what we're trying to illustrate):
Notice how much you've moved back from your address position (marked by the yellow lines). Doing that is making it more difficult for you to then get your weight back to where it needs to be -- on the lead foot -- at impact.
In order to stay more centered, you are going to need to feel like your trail (right) leg straightens more in the backswing and your whole right side (torso) stretches out as much as possible -- like you're trying to push your right shoulder up to the sky. That's going to give you some extension and cancel out some of that drift away from the ball.
Here's a more detailed discussion:
I would also look at trying to collapse your arc a little bit. Swing shorter and swing "tighter". Without getting too into positions, you can see on the left below how across the line you are at the top of the backswing. This means you have to get the shaft almost vertical in the transition and being that steep is just tough to pull off.
You are going to want to feel that your upper arms stay tight to your torso throughout the swing (you can practice this by hitting balls with old gloves or tees held in your armpits). You also need to feel a more inward component to your backswing -- that your hands are going back and up but also inside. I've shown on the right how you currently push your hands away from you as you take the club back, which is creating too much width and contributing to everything getting too long and loose and ungoverned.
Here's an older thread that goes into that in more depth: http://thesandtrap.com/t/30325/deep-hands-explained
Anyway, hope some of that is helpful to you and that you will stick around here. There's a lot of good information on the site.