I believe it is unusual in the sense that the tradition--there's no constitutional convention that I'm aware of--in the past has been that it was a private meeting of the Prime Minister with, in England, the Queen, and in Canada with the Governor General. I believe that practice may have changed in recent occasions, it would appear, from media reports. I wasn't there, but it appeared from media reports that others have been in the room. I don't know of any rule that says there can't be others in the room. Protocol would suggest it's the Governor General's choice as to who else is in the room. Protocol suggests to me it is. In other words, it would be, I would have thought, contrary to protocol for the Prime Minister to bring along a team of people to sit and watch what he's asking her for, but that's a matter of protocol. It's a tradition, that's all, and understandably so, because it is a matter that is private to the Prime Minister and the Governor General. I don't know if there's any rule of a legal nature or quasi-legal or constitutional convention that requires that.
On April 27th, 2010. See this statement in context.