This is a massive PITA for any users who exclusively use unique passwords and various unique addresses, as it sounds like the source of the breach(es) is unknown (so hard to judge which accounts would be affected without using Troy's sites to test everything or find some searchable dump online somewhere dubious).
That would be hundreds to check. While for the quoted users in the article all but one seems to have reused their password(s), suggesting fewer used overall so easier to check.
