I disagree, Lokno. I think that the Gameboy Advance will enjoy a long, profitable retirement much like the NES and Playstation had, but I think it's on the way out. We'll still see Gameboy games on shelves for years to come, and new games will probably be released through next year and into 2006, but like the NES and the PSOne, the GBA will be taking a backseat to the new systems by next Christmas. I believe this because I think the market is ready for more expensive handheld game systems...just look at the popularity of PDAs, iPods, digital cameras, cel phones and other handheld gadgets. Some of these are a lot more expensive than a DS or a PSP.
As for Microsoft's comments, I think the company is strategizing. If Nintendo loses the handheld part of the industry to Sony, that makes it that much harder for Microsoft to win. If Sony is #1 on the console side and Nintendo is #1 on the handheld side, that creates a balance of power that Microsoft can use to weaken both sides. Coincidentally, it's like playing Halo. When two armies of aliens are fighting each other, it's best to hide in the shadows while they take each other down, and then run out shooting at the winning side when you see that the losers are almost done for. Right now, Microsoft is still hiding in the shadows, but they just poked out to throw a grenade at Sony.