How many years until this generation of game consoles becomes obsolete and next gen comes out?

Its roughly 5-7 years. But you can expect near-future changes of the xbox 360 console. They are adopting Blu-ray technology (since that war is over) and are going to release a new generation of the xbox 360. It may look bad like they're copying the Playstation3, but I wouldn't be so y if I was Sony. Once Xbox 360 has Blu-ray, the PS3 is obsolete. Thats the only thing going for them right now. The Xbox 360 will be a (close to) perfect console. With the strongest online gameplay and support, the biggest game library, the largest user base, and overall best gaming experience, the xbox will rise up and take the entire market. (That is, if the Wii doesn't take over first.)