When will the PS3 and/or the Nintendo Wii go obsolete?

sony is coming out with motion senser and microsoft is coming out with project natal, those things will extend the lifecycle of each system, the wii has no new upgrades and i can tell you that if nintendo is releasing the 3ds, then they will probably be making a 3d wii because wii sales are going down because knowbody is buying it, they are all selling it, also, if you are afraid for the prices, the prices might stay at $299.99 for three years, or they might bundle something up with it to make it even more expensive!