If you're a leader, parent, attorney, teacher, physician, etc. - you are damaging your rapport and reputation if you point with your index finger. Siemens President and Chief Executive Officer, Peter Loescher, is shown here at a news conference in Munich. As I type this, I'm watching another news conference where the leader is pointing in this same manner. Regardless of the personality, position or demeanor of the the speaker - pointing with the index finger is always and negatively received by the audience.
If you have to point, point with the whole hand, palm upwards with your fingers loose and open.