By default of being queen she is "Her Majesty", and depending on which commonwealth country you live in, it states so in government documents (look in your passport), that of "Her Brittanic Majesty" or "Her Canadian Majesty" it a title of the head of state, which is inseparable from being queen. It is proper politic for her to be addressed as such. If the President of the USA can refer to her as "Your Majesty" surely it is acceptable for an online encyclopedia to do so.