I remember reading an article about Gears 2.That will see a new one every two years after the first Gears did so will and sold over 4 million copies.With this recent sighting on Amazon.com that say Nov 2008 is the month it will come out.

http://www.amazon.com/Microsoft-Gears-of-War-2/dp/B000ZK9QD2/ref=pd_bbs_sr_1?ie=UTF8&s=videogames&qid=1197996612&sr=8-1