Cmon guys, lay off him a bit! (unless there's some insider thing I'm missing out on, in which case I encourage you to carry on).
Either way, it depends on what you're looking for.
The DS has way, way more genre diversity in its games. Phoenix Wright, Advance Wars, New Mario Bros, Pokemon Diamond and so on and so forth. The PSP has more faithful-to-console games. It has some serious fighting games (Import Guilty Gear Judgment>all) as well as games like Metal Gear Solid: Portable Ops and, as you all know and love, Marvel Ultimate Alliance.
Both are haxxable, though. Flash carts for the DS allow you to download the games and play em. And the PSP has all that downgrader business.
Hax-wise, the PSP has alot more in the advantage department. The PSP can competently emulate the GBA, PS1, SNES, NES and so on and so on. Great stuff. The DS has the GBA, is all. Not that this is a bad thing, as the GBA is good stuff.
Ultimately, it boils down to which kind of games you're looking for. If you're looking for a combinaion of classical and unique appeal (there's more than enough in the way of non-kiddy DS games to the point where you can't label the DS as "kiddy") then the DS is it. If you're looking for portable versions of PS2 games with a big amount of haxxability, get the PSP.
What would I recommend? Being a tactical RPG and Fighting game fan (though I love all genres), the PSP looks better to me. The DS, though, is objectively the better of the two. (Another thing is that no PSP games last longer than 20 hours, which may or may not be a bad thing for you)