In the link are a couple of websites that go to various gaming sites that give small previews of the game, since they've already gotten copies of the game to try out.
Reading some of the previews, I'm doubtful of how much change there will be, in terms of visual and maps etc. from the demo. The whole asteroid belt and nebulous gas clouds will irk me, as will the relative size of the ground maps. As one of the websites said:
Overall Star Wars: Empire at War is already the best RTS-strategy game made for the franchise but as we hinted earlier that's not saying a lot.