No, Apple has to bother. A company is obligated to defend their patents and copyrights whenever and wherever they are challenged, or they eventually lose the rights because they will be deemed to have abandoned them.
Not so, and it really surprises me how many people get these distinctions in US IP law confused. Now, I notice that you are from .ca, and things may be different up there for all I know, so I forgive you.
But both Apple and Psystar are US-based, so any legal proceedings will be in a US court of law. What you are thinking about where enforcement is required is with
trademarks. Patents and copyrighted works in the US both allow for selective enforcement by the owner(s), so the owner is not required to press charges for every single case of infringement and can "look the other way" should they choose to. Trademarks can be
diluted, though, if not actively protected; at least such is the thinking behind that particular clause in trademark law.
I agree with the others who say that Psystar is going down. Whether you think Apple's EULA is right or wrong "morally" is not really the issue here. What
is the issue is that not only are they a party to software piracy per the terms of Apple's EULA, but that they are willfully using "Mac" in the name of their product. Even if you think there is a chance in hell that the Apple EULA could be overturned by a court (my prediction == not happening), Apple can make life tough for Psystar just with the legal time and $$ that they will be throwing at the trademark issue.
I also agree that it doesn't really look like this operation was set up by somebody or somebodies who thought the legal and business implications of their product through very thoroughly; there are many aspects of this that just scream "amateur." But I'm not sure that this business is necessarily setting out to make money, short- or long-term. My theory is actually that Psystar was started by a couple of Apple fans who are pissed off at the lack of a mid-range "headless" and upgradeable Mac, and stepped in to fill the void NOT because they thought they would be able to (successfully) pull it off for long, but to make a point and let the numbers of people on the internet who are commenting about it and perhaps even placing orders for such a machine do all the talking. They know Apple will retaliate; they
expect them to retaliate and are anticipating the moment that it will happen. They will willfully cease-and-desist when such a time comes, but will feel that they will have successfully "made their point" by then.
Whatever the case, this is sure going to be interesting to watch as it unfolds. I'll get the popcorn if someone else wants to pull the beer mugs out of the freezer...
-- Nathan