Liike Aussie2B said. If a system has no exclusives then what reason is there to even have the system.

At release the PSP wasn't worth picking up. I picked one up late 2006 once there were enough games released for it to be worth it, meanwhile having about 20 DS games. The PSP really started picking up and got a lot of great exclusives as well as some really good remakes making it my favorite system this gen. If all these games instead came to both the PS2 and PSP, then I wouldn't have cared about the system in the least.

That being said. If you want to play PSP games on a larger screen, there are component and composite cables released to do so. Unfortunately nothing for the DS but the system is still an awesome system.