Yeah, that pictures makes the post.
I love my PSP, but I'm not ashamed to say I barely ever play it. I have maybe half as many PSP games as DS games, and while I enjoy them all, it's true that exactly none of them are made to be portable. They all use a save system akin to a PS2 game, although there are a few games with background saving, like Ratchet & Clank.
I think the load time issue is largely the fault of the developer. I have quite a few games that don't have any (noticable) load times including Ratchet & Clank: Size Matters, God of War, and both Mega Man games. Sure, there's a little bit of load time between the menu screen and the start of the game, but while you're actually playing the game, loading isn't really an issue. This is not to say every game is like that. Silent Hill and Castlevania have too many load points, although both are supremely enjoyable.
It's tempting to simply put the PSP to sleep between sessions on the road, but doing so actually eats up battery life, which sucks. And now that I can play my PSP on the teevee, I rarely play it by itself now unless I'm stuck doing one of my medical treatments, at which point I generally bust out the DS because of its quick start-up time.