ThinkMojo’s Sebastien Lhomme provides some great tips for getting better camera animation in After Effects by parsing out the various attributes to specific components of a camera rig.

Quick tutorial, showing a few tips to better work with cameras in After Effects

Animating a camera in After Effects without even the simplest of rigs is really a futile effort, and Sebastien does a great job of demonstrating this showing animating a camera without a rig, and animating the camera using a simple rig.

Sebastien also shows how to use simple parenting and Expressions in After Effects, along with expression controls to create a nice camera rig that is highly usable and provides some slider controls.