In videos, you see a lot of rolling and falling. And I guess I can see where people would get the idea that ukemi is all about rolling and falling. But, IMO, the rolling and falling is the smallest part of ukemi. Rolling and falling is what happens when a person's ukemi skills aren't developed enough and there is only one option left -- disengage.
Coming from the role of uke, if someone's ukemi skills are developed enough, then there is no rolling or falling. You either negate the technique, take advantage of an opening, or both. (Unless one is in a teaching mode where uke is leading tori along the right path. But, teaching is a whole different world.) Only when uke finds himself/herself in a position where he/she couldn't receive the energy in a proper fashion, then uke must make a choice -- either get broken or find a last ditch effort to dissapate the energy. Rolling and falling does that to a certain point.
Why do you think there is randori? The interaction between two peers that goes back and forth until one can't receive the energy in a proper fashion and as such takes a roll or fall. When working with someone who is more skilled, then the lower skilled person tends to take more falls or rolls. Why? Because their ukemi skills aren't developed enough. If the skill level is high enough in both, you might not have much movement between the two players, but there certainly is a lot of ukemi going on.
I'm still learning this "jin" stuff, but my view is that ukemi is in line with what Dan, Mike, and Rob are doing. If you are uke, what is it that you are dealing with after your first initial attack? A response from tori. What response? Well, it is "aikido".
So, that response had better be "aiki". Your ukemi should equate to receive "aiki" with the body. That's the major part of ukemi. That is what gives uke choices and that is what ukemi is about. Not rolling and falling because at that point, there aren't many choices left.
My opinion anyway,