Minor bug but I figured I'd report it...
Forum accounts don't get created until the associated Ingress user logs in. This means you can tell who has logged in, which is not a huge deal.
However. the software seems to be smart enough to ban forum accounts for banned users -- again, only if they've logged in. Thus, if a banned user tries to log in, you can check their profile based solely on their agent name and discover whether or not they've been banned.