Not that the DS will outsell the PSP this year, but this statement:
"Sony's Playstation Portable (PSP) was the best-selling portable game console in 2005..."
Hello!! do your research, the GameBoy Advanced got 52% of the handheld console market last year, in North America alone.. the PSP did outsold the DS last year, but not the GBA.
In fact the GBA OUTSOLD any other console in the US in 2005, check it out: