The solution I found to closest match this problem was in using the Handles.Label function. It seems to do the trick.

using UnityEditor;

public class EditorClassName : Editor
{
    void OnSceneGUI ()
    {
        var _target = (Type)target;
        Handles.Label(_target.transform.position, "lblText");
    }
}

http://unity3d.com/support/documentation/ScriptReference/Handles.Label.html

+1 This is the ovious efficient way to do it :)

-1 nevertheless, it's bugged. Labels always show up, even when they're behing camera. This leads to weird messy and bothering things drawn on screen

regards.

Like this: http://forum.unity3d.com/threads/27902-Text-Gizmo