Caduceus or the Staff of Asclepius

Which symbol should we be using to represent the medical profession?

Apparently, the caduceus on the left, with two serpents coiling around a pole is mistakenly used by the medical profession even though the official symbol of the medical profession is supposed to be the staff of the miraculous healer-god Asclepius, a single serpent entwined around a cypress branch.

The caduceus is associated with Hermes (Mercury), the messenger of the gods, also known as the god of trickery, wealth and death! Whoops.

Caduceus
From a purely folkloric angle, it is impossible to ignore an odd fact that one finds in nearly every culture and throughout history: not only are staffs and serpents generally associated, but the juxtaposition or combination of the serpent and the bird symbols is almost always profoundly meaningful.
www.endicott-studio.com/rdrm/forcaduc.html

Caduceus vs the Staff of Asclepius
Most of organisations using the Caduceus symbol are generally either commercial or military (or American). Professional and patient centred organisations (such as the NZMA, in fact most medical Associations around the world including the World Health Organization) use the "correct" and traditional symbol of medicine, the staff of Asclepius with a single serpent encircling a staff.
www.drblayney.com/Asclepius.html

Caduceus - Rod of Hermes - DNA
As a symbol for medicine, the caduceus is often used interchangeably with the Rod of Asclepius (single snake, no wings), although learned opinion prefers the Rod of Asclepius, reserving the caduceus for representing commerce.
www.crystalinks.com/caduceus.html

Caduceus - about.com
Illustrated glossary definition of the caduceus, or wand of Hermes.
altreligion.about.com/library/graphics/symbols/bldefscaduceus.htm?terms=caduceus