I put together this Flash Player 9 Counter together using AS3 ActionScript Project in Flex2 that estimates the number of Flash Player 9 installations. I wanted to post the methodology and the source to be as open and transparent as possible. It was fun diving in and writing this widget in AS3 using ASProject. The output SWF file is 1360 Bytes.
Methodology:
1. Establish a rate for Flash Player 9 installations per millisecond.
2. Determine milliseconds since Flash Player 9 was released.
3. Update the value every 500 milliseconds
I will calibrate this counter this week against the exact dates and values but I am currently estimating that 2.32B Installs occurred the day of FlexCamp but it was most likely earlier. I will get this clear in a later post.
DOWNLOAD FP9Counter ASProject Source
Sure am glad 2.3+B Players can run this application.
Cheers,
Ted :)
DIGG IT! 
Ted, this is truly awesome!