Get a DS for strictly gaming. Go with a PSP if you also like to watch movies, listen to MP3s, etc.

Let me elaborate. In case you didn't know, PSP had carried a bad stigma all this time by Sony's own ineptitude. They figured they should cripple the PSP's video playback capabilities by limiting videos stored on Memory Sticks to 320x240 rez, at bitrate even worse than VCDs. They did so to hawk repackaged movies on UMD.

But no longer. A few months ago Sony came out with firmware 3.03 which has basically lifted this limitation. This means you can now create and playback video clips of 480x272 (native rez) encoded in AVC (H.264) with AAC. And with firmware 3.30 just released end of March, you can even play 720x480 rez videos, and as a bonus, get better PSOne support.