This post focus on the current state of play in IE8 Beta 2, what happens when you pull certain levers or the user pulls certain levers. For a given set of inputs, IE8 Beta 2 will generate a specific set of outputs. Mike've collated a table which may help us understand what's going on. The vertical axis represents different Meta tag / HTTP header settings while the horizontal axis represents normal vs compatibility view for both valid and invalid / no DOCTYPEs:

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