IANAL. But, although in principle, providing an easy opt-out shouldn't really matter with respect to copyright and so forth, as a practical matter it seems as if it does--in that, if you at least vaguely care about your website not being mirrored you have an easy way to prevent it. An organization like the Internet Archive simply can't afford (in terms of either time or money) to take a more aggressive approach to mirroring.
To be more specific--short of granting the Internet Archive some sort of special library exemption--what if I were to say, create a special archive of popular cartoon strips. What's the distinction?
[EDIT: The retroactive robots.txt situation seems less clear but, like orphan works, also depends on the scenarios you care to devise.]
To be more specific--short of granting the Internet Archive some sort of special library exemption--what if I were to say, create a special archive of popular cartoon strips. What's the distinction?
[EDIT: The retroactive robots.txt situation seems less clear but, like orphan works, also depends on the scenarios you care to devise.]