Nothing magical about it. Simple scale and opacity fade animation. the real trick is merely to design your artwork in such a manner that it will line up and then place the anchor points strategically, because that will be the origin of the scaling.
Can you give an example?
Place the anchor point at the spot you'd like to zoom in to. This will be easiest using the Anchor Point Tool (hit Y), which allows you to free-drag the anchor point to the desired spot without moving the layer. After that, it's as simple as making some scale keyframes.
If your art is made of multiple layers, it would likely be easier to either Precompose them and use the above technique, or to parent all to a Null, placed (before parenting) at the spot you'd like to zoom in to.
If you're still confused, it would likely be helpful to check out some basic AE tutorials, to better understand how the program works.