I browsed forums.anandtech.com on a psp. Not fun at all. Cellphones hvae 200x better interfaces as far as typing and navigation. Also its actually suprisingly slow even thougn its on broadband, almost like it's not no 802.11b standards but maybe 56k. Then there si the fact webpages are compressed in format to fit so nothing is where it should be nd dont even get started with websites with frames. The whole internet browsing is complete worthless bs. you need to be clost to a wifi hotpoint to do it and even then you might as well boot up the pc, it'll be faster to boop up the laptop rather than just try to log in to a website with a psp.
I see both as sorta silly. The PSP really is jack of all trades master fo none. Internet is slow, 4gbs of memory costs you $130 so as a 3.5gb mp3 player it would cost $380 and the games are okay but I havent play any that draw me in or interest me.(Burnout, NFS: Rivals, That everquest action/rpg,SOCOM, Infected). Also if you wanto to play wirelessly like gameshare( 2 psp play together with only 1pspneeding a UMD) with Buirnout takes 10 minutes to load 1 race, and not menus mind you, 1 black loading screen for 10 minutes and when the race is over, restarting the race with the same opponent take another 2 minutes of loading screen.
The DS has fun games(mario, mario kart) bu the graphics are nothing special and it dosent have the multimedia capabilities of the psp.
If it was my choice, I'd go for the one that plays better games(DS) over the one that does everything half arsed.
<- coming form the guy that said before the 2 launched, "psp kicks arse and DS sucks, it's a gimmick no one will buy and I woyuld never be interested in."