Both the cracking and the publishing...
>>>There is arguably *some* difference between someone doing something on hardware they've bought, with the intention of only using what they do to enable their own alternative use of the hardware, and telling other people how to do something if revealing that knowledge enables illegal activity.
That second case is a potentially very murky area, especially if what is being done has some arguable merit (like in this example, reinstating the Linux capability, the presence of which might have motivated some people to become owners).<<<
You have it somewhat backwards. Publishing information and offering services is generally allowed if it has legal uses (cf all P2P). It has to *only* have illegal uses to be illegal.
However, this falls under the DMCA because Sony can claim that the PS3 was crytographically secured digital material (whether it was well-secured or not is immaterial under DMCA). Simply bypassing the code even for personal use violates the DMCA unless it is one of the exemptions issued by the LoC (iPhone jailbreaking is legal but PS3 jailbreaking is not).
Yet another example of why the DMCA needs to be abolished (but never will be because Congress is thoroughly bought and paid for by the big corps).