>According to Tesla there is a fatality every 94 million miles (150 million km) among all type of vehicles in the U.S.
>By November 2016, Autopilot had operated actively on hardware version 1 vehicles for 300 million miles (500 million km) and 1.3 billion miles (2 billion km) in shadow mode.
Those numbers are 9 months old and only apply to Autopilot v1 and not the Autopilot v2+ introduced late last year. I wouldn't be surprised if the current number is in the 500+ million mile range with only a single fatality. The sample size is obviously small, but there seems to be a clear improvement over manual control.
[1] - https://en.wikipedia.org/wiki/Tesla_Autopilot
EDIT: With chc's and my post we have 3 numbers and dates for reported Autopilot miles. Projecting that forward at a linear rate (which is conservative given Tesla's growth) would put us at roughly 750 million miles today.