Coming straight from the Halo Wars community website at www.halowars.com I can report that the eagerly awaited Halo Wars demo is now available to download for Xbox Live Gold customers and silver customers a week later. I strongly recommend checking it out!
There’s also a new Halo Wars trailer which you can see here: http://www.xbox.com/en-US/games/viewer.aspx?productId=1898&assetTypeId=2&shotId=6
And also an instruction manual here: http://www.xbox.com/NR/rdonlyres/31804095-7B32-4CE2-A17E-3CB54A3692EF/0/HaloWars_MNL_EN.PDF
In the words of Ensemble Studios “Have fun and good luck“