Yep, much good ground has been covered here. DSLRs are great, but they do have their limitations.
It's true that they really don't respond well to sudden jostling (like if you're shooting from the back of a truck and you hit a bump in the road). Technically, I don't think that's jello. As I understand it, jello is the way that vertical lines get bendy whenever you do a whip-pan. Regardless of what we call it though, the effects that result from the camera being jostled are not pretty.
I personally find moire and aliasing to be more annoying. I never notice it until post, and by then it's too late!
Overall, though, I think these are very minor obstacles that can be avoided with proper planning. For the time being, I still think they're the best poor-man's camera.