Perhaps something like the "Debian package Popularity Contest":
http://popcon.debian.org/
...
The popularity contest project is an attempt to map the usage of Debian
packages. This site publishes the statistics gathered from report sent
by users of the popularity-contest package. This package sends every
week the list of packages installed and the access time of relevant
files to the server via email. Every day the server anonymizes the
result and publishes this survey. For more information, read the README
and the FAQ.
...
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Jeffrey Hundstad
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