Nelliemoser - I love the gay cake converted bread rolls to homosexuality picture. I see no reason why the men couldn't picture the sesame characters along with their chosen slogan. It's illegal to discriminate on the grounds of sexuality so for me, case proven. I have pondered the question raised by a number of posters about what would happen in a similar case if the bakers were asked to decorate a cake with abusive messages to an ex partner, or in praise of Isis as suggested earlier.
I suspect that as such messages would not be illegal but may be seen as threatening or in bad taste, the baker's would legally be able to refuse to take the work. Do we have any lawyer's who can clarify.