I have yet to actually see a PSP. I wasn't interested in a DS until I played it for a weekend. Then I found it to be an excellent idea that is well implemented. The PSP is too expensive, too fragile, and has too short of a battery life for me.
DS w/ game (Mario 64DS): $150
PSP w/ game (Ridge Racer)+memory stick (32MB): $290
Now, if you want to actually do that movie watching and all that, you have to drop another $100 for a memory stick or re-buy all your movies.
I'm not ready to have a fragile $400 device hanging around in my pockets yet.