I have no idea who first created the goal of taking 10,000 steps per day, and Google won't tell me. But that goal has become very popular.
Curious, I purchased an inexpensive pedometer after reading that these can be attached to your shoe while cycling.
Today I wore it all day for the first time. Bicycling to work logged 2,300 steps. Bicycling home logged 2,500. In both cases I rounded down since bumps in the road must have generated some false counts. I know there were not too many false counts since I checked a few times along the way while counting my pedaling, and because I average more than one pedal per second (and 60 sec/min * 30 min = 1,800 sec). So even being on the conservative side I can can use 2,100 steps for each direction of the commute.
While at work I took 5,300 steps. Here the pedometer was on my waist, and accurate.
So that's 9,500 steps and it's not even dinner time. Hooray!