One thing I learned real quick with these devices is just because it was like that from the beginning does not mean it is not a software issue from a bad install. Reset and Restore are the first basic troubleshooting steps in trying to figure out issues with iOS devices new or not.
Anyway I guess I misunderstood your issue which I thought your camera was always zoomed in. What you are seeing I suspect is normal. I never really looked at it till now, but I see the same thing with both my iPhone 4 and iPad 3's cameras. The camera is capable of taking much larger resolution photos than it can video. In the iPads case, the 5mega pixel photo is 2560x1920 where the HD video is only 1980x1080. To use all the pixels in the camera's sensor for quality video I suspect you end up with a zoomed in effect or they may also be cropping the image for video taken from the sensor capable of larger images which would also zoom it in.
My explanation is probably all wrong, but I'm sure the issue is the difference between the resolution of the video and photos. But I can confirm I see the same thing on 2 different iOS devices.