Get the darn light baking progress:

        public IEnumerator TrackProgress()
        {
            /*
            AsyncOperation async = (AsyncOperation)Lightmapping;
            while (async.progress < 1f &&
                !async.isDone)
            {
                m_progress = async.progress;
                yield return async;
            }
            m_progress = 1f;
            yield break;
            */

            Type type = typeof(Lightmapping);
            foreach (FieldInfo fi in type.GetFields())
            {
                Debug.Log(string.Format("Detected field: {0}", fi.Name));
            }

            foreach (PropertyInfo pi in type.GetProperties())
            {
                Debug.Log(string.Format("Detected property: {0}", pi.Name));
            }

            foreach (MethodInfo mi in type.GetMethods())
            {
                Debug.Log(string.Format("Detected method: {0}", mi.Name));
            }

            yield break;
        }