What is the average human reaction time is?

Depends on a lot of factors.

Perception to finger movement is somewhere in the ballpark of .215 seconds "average".

Average range is something like .14 to .33 seconds.

Reaction times as low as .1 seconds are likely possible but hard to measure consistently.

Reaction times below .12 seconds would make you part of an elite minority.

Some resources to check out:

www.humanbenchmark.com

Normal distribution of reaction times on a specific task.

www.visualexpert.com/recources/reactiontime.html

Good rundown of factors that influence "reaction time".