Problems with Camera TrackTo Constraint

I’ve got a really basic soft body project I’m working on. Everything looks great except when I try to set the Camera (TrackTo Constraint), it doesn’t follow the animation. It stays fixed at the origin of the object. I think that’s what it’s called. The single vertex thing that controls the location of your object in object view?

By default a Tract to constraint tracks the Center of the object. In the case of a soft-body, the center does not move as the soft-body deforms. However, you can assign a vertex group to your soft-body (in Edit mode) and then use the Vertex group name in the VG field on your track To constraint. Because the vertex group moves as the soft-body deforms the camera will track the way you want it to.

More info on Vertex Groups here: http://wiki.blender.org/index.php/Manual/Vertex_Groups

Update: I assigned the vertexes of the soft body object to a separate vertex group, and in the TrackTo constraint I added the vertex group, but still no luck. In edit mode when I view the animation it doesn’t look like any of the vertexes are moving. Any ideas?

see update.