Even without a Gears of War demo it did just fine with 4.5 million sales worldwide. Developer Epic’s Tanya Jessen has said that: “[There are] no plans for a [Gears of War 2] demo. The reason being that it’s been such a fast turnaround. A two year production cycle, for a game of this caliber, is really short.”
She continued: “Our focus is always on putting out the best possible game we can. Whenever you do a demo, you have to basically ship a whole separate product. As far as our plans after we ship, I can’t really speak to that.” So there’s still a chance of a demo after the November 2008 release of Gears of War 2. — Via Shacknews