Syntax: %USERINFO{format="$username is really $wikiname"}%
Expands to: guest is really TWikiGuest.
The tokens $emails, $username, $wikiname, $wikiusername, and $groups are available for use in the format string .By default, the info will be formatted as a comma-separated list of the username, wikiusername, and emails.
To get information about another user:
Syntax: %USERINFO{"TWikiGuest" format="$username is really $wikiname"}%
Expands to: guest is really TWikiGuest
The parameter should be the wikiname of a user. You can only get information about another user if the {AntiSpam}{HideUserDetails} configuration option is not enabled, or if you are an admin.