The intent of the Act is to prohibit any marriage to a non-Anglican, which would threaten the supremacy of the Crown as Head of the Church of England. Unless it is repealed or amended, no future heir to the throne will be allowed to marry anyone who has not embraced the Anglician faith.
If the Act doesn't say that a non-Anglican may not become Queen or Prince Consort, then the intent isn't relevant nowadays when Protestant and Catholic aren't the only options. The Act specifically excludes from the succession anyone who marries a Catholic; it says nothing about Lutherans, Orthodox, atheists, Jews, Muslims, or any other sect, religion, or worldview.The monarch has to be a member of the Church of England as long as Britain has an established church; the Act doesn't require that the consort be anything other than not Catholic. Nobody has had to give up his or her position in the line of succession, at least in the 20th century, for marrying anyone other than a Catholic. And even people a long way down the line of succession have to give up their place when they marry a Catholic.
http://www.guardian.co.uk/monarchy/story/0,2763,407239,00.html
IMO, it's about time they did what it takes to repeal that Act. It's a piece of blatant religious discrimination that must be highly offensive to Britain's Catholics.