hi raca,
I suggest that on the install of pacman, install scripts should be suggested the install of pkgstats to help more people using it.
i'm against. it is already easy enaugh to install & use it. and btw it needs time to setup one's arch installation - statistics of newly installed systems wouldn't be that meaningful, don't you think?
Anyway, I think a better way would be the mirrors making the statics of downloaded pkgs so it would be less intrusive and less risky. But that would require a lot work on mirrors and statics would be bias because it wouldn't know of pkg that are installed and uninstalled right away.
to the contras ou already mentioned, there should be added: -many people have their own mirrors -some people are reinstalling packages from the mirrors (those not using the cached pkgs)
Another thing that would be nice to now about is if the packages are really used.
call me paranoid, but i don't want others to know what i'm exactly doing with my computer! regards Hubert Grzeskowiak