Newborn to 3 months:
Your baby can see your face clearly when you're feeding him, but probably not much farther than that. Good news, since babies prefer to look at human faces over anything else. He'll also see high contrasts (like black and white) best.
3 to 6 months:
At this stage, he can focus on things as far as 15 feet away by around 6 months. His eyes can also follow moving objects, and he's better at telling colors apart and has stronger depth perception. Go for bright blocks and books.
6 to 9 months:
Now his eyesight is becoming much more like your own. He can distinguish even subtle colors. If you don't already have a baby-safe mirror in the crib, get one: With his improved ability to focus, and his interest in other babies, he'll love it.
9 to 12 months:
You can see your baby's eyes and brain working together: If you show him something, then hide it, he'll look for it. Soon, if he sees a toy across the room, he'll go after it!