Following is Nathan's official remark:
The solution we have set in place will take care of that. It should be live shortly, as it‘s already being integrated and deployed. Then when it gets activated, I really hope you haven‘t tried to cheat in the past. Bans are irreversible and become part of your Steam game bans.
Oh, it apparently also tracks and links together people and their alt accounts, sounds good in theory, less manual work for us to track down and maintain a list of alts and the real steam accounts they are linked to.