There are reports that protesters stepped in to protect the Egyptian museum before the Army (which is held in much higher regard than the police) secured the building with armored vehicles. Apparently, no one wants a repeat of what happened to the Iraq Museum. We'll keep our fingers crossed that the museum and its treasures stay safe.
Update: STRATFOR is reporting that Egyptian Security Forces have withdrawn from Tahirir Square, the location of both government buildings and the Egyptian Museum. If so, the Museum may now be unguarded. The situation remains confused so it is unclear if this is true or not.