Oh yeah, trying to use a nip05 someone else has registered won't validate, at least it shouldn't (the client should verify it against the users' pubkey used in the app). Adding a spam label would add another level of awareness 👍 

 @Vitor Pamplona @jb55 

 But this won't stop them from registering a similar nip05, which is what I was referring to when I mentioned address as a service websites.