However, isn't gameObject.transform the transform between the world coordinates and the gameObject?

Correct. But that's your starting point. Then you need to get the Camera matrices as well and then you can combine the transform matrices together so to go from object to camera coordinates. That's part of the Unity API (see also the Camera API), it's not something specific to Vuforia.

Thank you, that is helpful. However, isn't gameObject.transform the transform between the world coordinates and the gameObject? I'm specifically looking for the camera position based on the individual tracker pose. I'm using FrameMarkers, and would like to get a camera position for each one. My linear algebra is a little rusty, but don't I need the camera perspective matrix and the gameObject to world coordinate transform? It starts getting a bit more complex after that. 

Hi, the article you are referring to is only applicable in native code (Android or iOS), but not in Unity.

In Unity things are much easier, as you can get the Trackable pose directly from the transform of your trackable object.

For instance, if you attach a script to one of your ImageTarget, you can just retrieve its transformation using:

this.gameObject.transform;

(this.transform should also work)

Then, once you have that, you can manipulate it in the way you want, using the Unity API (not the Vuforia API).

See:

http://docs.unity3d.com/Documentation/ScriptReference/Transform.html

http://docs.unity3d.com/Documentation/ScriptReference/Matrix4x4.html