All this talk about wiretapping, wikileaks, hacking and such makes some of us, very edgy.
How can you tell when your camera is active on your Macbook Air?
Next to the camera at the top, middle of your screen is a very small led indicator that comes on when your camera is active. It is pretty hard to see this hole when not active.
To see the green light - try running PhotoBooth application and you should see it.
If you fear someone might be watching you, try putting a post-it-note over the camera.