  This article reviews and updates the Standard Model prediction of the tau
lepton g-2. Updated QED and electroweak contributions are presented, together
with new values of the leading-order hadronic term, based on the recent low
energy e+ e- data from BaBar, CMD-2, KLOE and SND, and of the hadronic
light-by-light contribution. The total prediction is confronted to the
available experimental bounds on the tau lepton anomaly, and prospects for its
future measurements are briefly discussed.
