As we have both remembered the fleet of Emperor Mengsk is eridicated by the Zerg Queen(The Queen of Blades) at the last stage of the Starcraft Broodwar.In Starcraft 2 we are waiting any action from Emperor Mengsk maybe he will assemble a new fleet to assault any other forces near his border planets.Or he is designing a very evil tactical battle again.The definite answer will be ofcourse in Starcraft 2 storyline.At the picture you can see an female character near him which will probably be a ghost like Kerrigan.She is in cloak mode and ready to kill!