1UP: Preview, by Scott Sharkey: "It's not going to change the world, but it looks pretty good as expansions go."
3D Gamers: Includes information, news, screenshots, and downloads.
GameSpot: News, previews, images, videos, links, and a forum.
GameSpy: Previews, screenshots, and a movie.
GameStats: Videos, screenshots, and article links.
IGN: Screenshots, videos, previews, and a message board.
Wikipedia: Article, including a feature list, new units, and the plot.