This is one of the sites I kept up with for a little bit for DS information. They also have a PSP page to go with it.
Here is the PSP launch date with the price and the line-up that is coming with it. So far it is a lot better than the DS launch line-up. Actually Metal Gear: Acid and Twisted Metal: Head On own the DS line-up by themselves. I'm kind of excited about Twisted Metal but I am also excited about
this. Cleary Nintendo needs to get their heads out of their asses and make some online capabiliteis for some games.

About the only way I see DS beating back PSP is if they make some games like PSO and make them online. Twisted Metal online though? How cool would that be sending a nice size missle to your friend's car? We'll just have to wait and see what happens though, but as of right now PSP > DS.