Like, I believe it's a 6-in-1 unit, is it not?
Think of it this way, PSP is a jack of all trades, but master at none.
My main beef with the PSP as a media device is that it's too big to slap into my pocket and carry it around without worry like you can with an iPod, and even when watching UMD movies, they drain the battery-life like you won't believe....
(not that the DS doesn't fit in your pocket either, but it's not like you play games in your pocket anyway)
(of sorts, at least it uses Wi-Fi and connects to the Internet)
And the only main reason to do so would be for surfing the web, which is excruciatingly slow on the thing, I had a better browsing experience on a 486 computer running Win95.
I just bought the thing for the games 4 months after its launch date, and at the rate the good ones are coming out, it'll be awhile before I pick the system up again.
Overall, it's not that I'm bashing the PSP, its just Sony tried to sell the machine on functionality it just can't excel at with regards to the competition, even if it is a somewhat "all in one" device, as you call it.
(they should have just focused the device on the main reason it sold at all, the games)