Let me just say this doesn't really mean anything other than for a week right now, the
PSP outdid sales of the
3DS. It doesn't mean that the 3DS is a failure or that its popularity is waning. It's just a one week look.
Kotaku
has data from Media Create showing that for March 28 to April 3, the PSP sold 57,379 units while the 3DS sold 42,979 units. That's still good for second place in hardware sales for the week, but we'll see how it does in the long run. There were some games coming out for the PSP that week that pushed it to the top. We'll see how it goes once there are titles that are released for the 3DS that's in demand.
That said, I don't have a 3DS nor am I going to pick one up. I enjoy 3D and all, but I barely touch the DS and the Wii's been off forever so I don't feel like spending more money on a system I probably won't play.