Sony had a 30% handheld share to Nintendo's 70% this week. This is also the 4th straight week psp sales have gone down. I could actually see it actually battling it out with the GBA at around 15K within the next couple of weeks, even before the arrival of Mushiking. When that does arrive, it'll be very interesting. Also, if it already has 400,000 orders, that could put it at a challenger for 2nd biggest handheld game behind Pokemon and competing with Megaman EXE.
The only problem is, if the psp gets owned hard by the DS just going along as it is, and the old GBA pushed by an unheard of kids game, it's going to make the Pokemon DS + Gameboy Micro megaton ownage a huge anti-climax.