CBS/P can shut anyone down at any time at their discretion. The guidelines simply advise that anyone meeting the guidelines to the letter is most likely safe from action from CBS/P at the present time. They could change their minds later depending on any number of considerations. On the flip side the guidelines do not say they will automatically go after someone who does not follow the guidelines to the letter. From that we can deduce that things are not much different than previously and I think this will be more broadly realized as individuals "push the envelope" (so to speak) to see what will be tolerated. CBS/P, through John Van Citters, has already stated that CBS/P would express any concerns with a polite phone call first, likely a C&D letter second and then hardball action as a last resort. This will allow any potential violator to clean up their act before things get unpleasant.I am a bit surprised that a fan production meeting all the guidelines and not materially different from others could be picked out for a lawsuit solely based on the studios' whim.
I think the real intent behind the guidelines is to put folks on notice to scale back their aspirations. And not necessarily quite as restricted as the guidelines appear to suggest.