Last modified: 2013-04-19 10:17:45 UTC
It seems that the list=users and list=allusers have some overlap in functionality and I believe they should be a single module. I'm not quite sure about this though so I'm going to start this bug as unconfirmed.
The real difference is in how the users to be listed are selected: list=users takes an explicit list of usernames, while list=allusers lists all users by default and filters the list using aufrom/auto/auprefix/audir/augroup/auexcludegroup/aurights/aulimit/auwitheditsonly/auactiveusers. It's a little like the difference between using prop=info&titles=... and prop=info&generator=allpages. They could possibly share a class, much as list=backlinks, list=embeddedin, and list=imageusage all use the same 'ApiQueryBacklinks' class, but I'm not sure how much sense it would be to try to put both a parameter like ususers and parameters like aufrom/auto/auprefix/audir/augroup/auexcludegroup/aurights/aulimit/auwitheditsonly/auactiveusers on the same user-facing module.