Reading all these comments is very disappointing, especially the people demanding recalls. People are far too quick to call foul over something incredibly minor, and correctable through post editing (if you're taking serious photos, you'll always post edit).
The dot you're seeing is a reflection off the lens, and is normal. I went back to my photos and have had some reflective dot since my 3GS, as well on my DSLR, and a Samsung point and shoot.
It can happen on literally any camera. The lens and the angle of light is what determines it. If the lens has a hood or a shadow cast over it, you'll see less ghosting. This is a non-issue.