Hi FlexWS.  This is currently available.  Log in as a Domain Admin and then go to Reports >> Domain Summary Reports >> Traffic Reports >> Disk Usage.  

Here you'll see all domain users, along with their max disk space / disk space used.

 

That is correct, but I'm looking for this list (as global administrator) covering all users on all domains in one list.

Also: In a specific domain's users list, the total below the "max diskspace" column counts the diskspace of all the individual users, but that isn't true, since the domain can have a different max diskspace limit. Showing the domain disk limit over there would be better?

We could use this feature as well.  We have 170 domains on our server.  I really don't want to run the same report 170 times.  Or better yet, I would like to run a report that shows me all users over x% of their current quota.  The report would show me user name, domain, disk used and max disk.