Yeah, this has been all over the news here this afternoon. Charles and Camilla can't be married in a Church of England ceremony because she's a divorcee (he's divorced as well but being a widower supercedes that) who's ex-husband is still alive. They're being married in a civil ceremony and then the Archbishop of Canterbury will bless them. The latest controversy is whether, once Charles becomes king, and therefore head of the Church of England, the Anglicans will support his non-Church marriage.
Upon receipt of the throne, Charles will be king, Camilla will be HRH Princess Consort (yes, she does get the HRH). There were early reports of her getting a different Duchess title, but that seemed sticky when it came to inheritance.
As far as titles go, had Diana still been married to Charles and still alive when he took the throne, she would have been Queen Consort (like the Queen Mother before her). If there's a female HRM Queen, her husband retains the title of Prince so that he can't take the crown after she dies.
I don't really care one way or the other - if they're happy, AND his sons are happy, great. But for now, long live the Queen.
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