For the sake of brevity I will keep this as short as possible. The main points up top, the arguments below.
Background:
CopyBot was a short lived piece of software that captured the ire of the content creation community when it bypassed the Second Life permission system.
Detection:
Detection of CopyBot is not practical or unmaintainable (easily bypassed or tricked). Its only a matter of time before a computer can pass a Turing Test. If you make your Turing Test too hard, humans will fail it.
Solution:
The solution is to condemn copyright infringement and remind people it is illegal.
All other solutions are technically infeasible or unmaintainable; a waste of time & money.
If it can be engineered, it can be reverse engineered.
None of the possible solutions address the core issue, only postpone its resolution. Postponement is the only resolution.
Core Issue: CopyRights vs Property Rights
In Second Life, property rights and copyrights are in direct contention in the minds of it's users. SL is a place of property governed by copyright (the old ruled by the new). Property rights and copyrights will take a long time to reconcile. Everything is effected by copyright and/or property right law, which means everything ever created is in contention (and that is a lot to weigh in and sort out). The only way for both property rights and copyrights to be truly reconciled is with a Utopian society, or its complete inverse.
When the copyright laws were first drafted, the computer was not even in fiction; there were no books with computers. They was no way for these laws to have been drafted with computers in mind. Property rights and copyrights differ drastically, like Yin and Yang. Property rights are based on the principle: once you have it, you can do what ever you want with or to it. Copyrights are based on the principle: once you have it, you can only do to it what you have permission to. The purest form of each doesn't work. Nobody wants anything they have to be constantly asking permission, so copyright has Fair Use built into it. Property rights have similar limits, you can't do what every you want with it (just because you have a gun doesn't mean you can shoot your neighbor).
There is always a push to change both property & copyright law, there are those who want more rights and those who want less. Everyone wants there rights to be protected. There is no way to fully automate this protection (you can outlaw it but that doesn't stop the bullet from killing you).
Final Thoughts:
Fully automated protection in SL is impossible. If it can be engineered, it can be reverse engineered. LL can make things easier or harder but they cannot stop copyright infringement (without stopping the creation of content).
SL is ruled by copyright. Copyright infringement is a crime.
If it happens, report it, bring them to the attention of the authorities.
The use of CopyBot or any other method or means to steal content is ILLEGAL.
The use of CopyBot or any other method or means to use content with in Fair Use is LEGAL if the method or means have been cleared with Linden Lab (DMCA reasons).
In Second Life there is no Yin and Yang, the black and the white, not even shades of gray, only Technicolor. Neither property law or copyright law fit perfectly with SL; It is that dichotomy that leads to drama like that of CopyBot, Prim Mirror or any of the other previous fiasco's. This imperfect fit will lead to drama in the future. We live in interesting times.
For further reading:
Wikipedia: History of copyright law
Raph Koster - CopyBot