However the present system of website logins is a mess and should be fixed by using a voluntary identity management system.
Cnet reports that Comcast have a similar initiative where they disconnect users with infected PCs. This is also problematic, but it sounds a little better becasue it's good internet citizenship not to act as a springboard for internet criminals.
Realistically spaking, the responsibility for PC security remains with the vendors, not with the users as long as the systems are too complicated to be fully managed by the end users.