Well, having owned a DS, I find myself enjoying the PSP more. Don't get me wrong, I liked my DS just fine. However, the lack of titles is a severe turn off. Even four months or so after release, there's not a huge selection of titles on the system, few that are appealing to me, and even fewer that are truly innovative.
The PSP has a wide range of games, and while the system doesn't feature a touch-screen, and so it lacks the "innovation" the DS promises, I found several games at launch that appealed to me, and that makes the PSP more appealing to me overall, at least now.
As far as wether or not it "blows the DS into the wall" in other areas, I suppose that's subjective.
While I don't place much importance in graphics, a suprising number of gamers do, and I feel that the PSP has the DS beat in that area. It features graphics that are close to PS2 quality, which is leagues ahead of the N64 quality graphics the DS is capable of displaying.
In terms of features, I believe it has the DS beat there too. While the DS very well may get the ability to play video somewhere down the road, wether in the form of an add-on or a series of video carts like the one's Majesco released for the GBA, the PSP affords me the option of putting my own video on a memory-stick, and I can do it right out of the box. I can also put MP3's and pictures onto my PSP, giving it quite a bit of value beyond simply playing games. Even if I get tired of the game selection, the ability to put movies and music on my PSP assures that it'll never go unused.
Now, I don't want to come across as sounding like I'm anti-DS. In fact, I like the DS. I just feel that it hasn't even begun to live up to it's potential, and that four months after it's release, the dearth of compelling titles is pretty discouraging. I'm of the mind that Nintendo should've held off on releasing the system until they had a full compliment of titles ready for it, and that releasing it beforehand was a bad idea. I can understand that they wanted to hit the Holiday rush, and despite their assertion that they don't see Sony as competition, I'm pretty sure they rushed the system out to beat them to market as well. I wish they hadn't.
Eh, anyway, I'm going to cut this short. I have far more that I could say on the matter, but I'm too lazy to say it. Plus, I think I've said too much as it is.