I finally got an xbox360 dev kit today, and was able to see how well it interacts with the PSP. It worked great - I was able to listen to mp3s right off the PSP through the Xbox360 Music Player, and view images from the PSP at full screen.
Anyway, here's what it looks like in the Xbox360 Dashboard - click one of the thumbnails below to see a larger image:
PSP Vault
PSP Vault