Your iPad has what is called iFace Detection and is supposed to auto focus. Of course in low light, this has proven near impossible. In bright light, it works quite well. If, in bright light, your camera does not auto focus, I would make an appointment at the Apple Store Genius Bar and if they determine your camera lens is not working properly, they will replace your iPad.
Well it doesnt focus in bright nor in low light i have to touch the screen for it to focus in video mode.....but for me that really isint a big deal....it focusses automaticly in picture mode, and thats what i really care about....but i have just returned two ipads for having wifi issues and yellow screen issues......the one that i have now has a perfect screen its whiter than my ipad 2 its just perfect and i really dont want to risk taking it back and getting a new one that may have some sort of yellow on the screen....i was just courious about the whole video focusing deal.....but ill be fine and it really isnt a big deal ....but i will take it to the apple store when ever i have a chance thoo....and see what they say about it....