Freedom vs. Freedom
DSF Internet is now working on a new version of their client and I'm sure they'll make sure that this time they get things right. After all, there's going to be a whole world out there analyzing their code to ensure that it is completely legal. Here again I'm wondering about the effectiveness of the protection provided by the GPL. What if they've learnt from the GPL'ed Everybuddy code and have now written brand new code, which differs enough from the original code. This time DSF Internet has a moral obligation, but not a legal one, to release the source. With software there's always more than one way to do your code.
The GPL protects code not ideas
We cannot deny that commercial success is a tempting goal. That will happen and you can argue that in the above case, had it been the BSD license, DSF Internet would have got off the hook relatively easy by just having to include the copyright notices and license. Does it matter in the end? The crucial link in the chain is detection. How does one exercise the GPL if they cannot detect the violations?
I don't believe that this was a failure of the GPL, however. The GPL was created to protect against such un-ethical behavior, but let's face it, if people are going to be un-ethical enough to blatantly steal from Open Source, you can also trust them to be un-ethical enough to not care for the license. At the end of the day, the license is nothing but words that can be easily ignored.
Licenses like the GPL aren't the answer to the problem of plagiarism. The answer is the Open Source community. The ssh case perfectly highlights this important point.
The ssh case
The ssh protocol as developed by Tatu Ylonen was first released into the community as an Open Source project. It soon became very popular as everyone saw the importance of this new protocol over insecure protocols like telnet. Many people joined in the development. But soon Tatu Ylonen changed the license to a more restrictive one and also started a company for commercial distribution and support of the product.