HTML 5 DOCTYPE

So it turns out that IE8 will trigger "IE8 Standards Mode" for at least the HTML 5 DOCTYPE, and according to Chris Wilson "any unknown DOCTYPE".

This makes the proposal of the element a little more palatable, but I still feel it isn't enough. 

What I'd really like to know is do XML and XHTML MIME types trigger standards mode? And are there are any other DOCTYPEs that will trigger standards mode?

Based on currently available information, I don't feel like the HTML5 DOCTYPE is enough... if Microsoft would just be more forth-coming with information then I don't think this would be nearly the issue that it is.  There are a lot of unanswered questions that any one of the IE team members could have spent five minutes on a blog post answering.  And speaking of the closed nature of Microsoft,  Molly Halzschlag has posted a blog article on this very topic.