Well... it's not the first time something like this has happened. GM did the same thing with all the Corvette shops, etc. They own the name. Any intelligent business owner should know not to call their company "Corvette Mike's" or something like that. The gas station named "Mustang Mart" could argue that they are referring to the type of horse, not the car if they are in an area indigenous to the animal... Afterall, what is Ford going to do - make us change the namesake animals' name because they trademarked it? Sue American Indians for riding their Mustang horses? Maybe Turtle Wax should sue to make us all stop calling the little hard shelled critters by their actual name and come up with something else...
Like anything else, what is required here is "common sense". Unfortunately, maybe someone already trademarked that phrase so we can't use it anymore.