The way of the roll, this holds special signifcates to me mainly due to the fact that my main system that I train in is an aikido based system and the first year of my leasons I wasnt allowed to do a single throw. I was used as an uke, or punching bag in english for the more senior students training and the teachers prime demostratee (if thats a word).
But because of this type of training I learnt the techniques by name, the differnce between a good throw and a bad one and later on where to counter safely, sooner then those of the same grade. Now I try to focus most of my classes on how to attack well, keep yourself safe through out movement so that if an attack fails and you are thrown you can still be better off......well kind of.
So the way of ukemi isnt the way of falling over or falling victum to someone countering your techinque. Being a good uke is like being a good actor, you must know the intention of the attack that you are preforming. A simple punch can take on many form and change the way a techinque is preformed depending on the intention of that punch. Sometimes your punch is a jab (quick, on target but can be used as a distraction, a way of covering the line of sight and a way of measuring distance for a more powerfull technique) or a powerful haymaker one hit kill (in the hope of rushing a person to overwelm their mind aswell) or drilling gaurdbreaker thats rotation and weight gets into the small gap left in a particular gaurd. As the person making the attack (uke) for that training seasion you must know the proper intention of your attack so that the person preforming the counter (torii) gets a sense of where the particular throw lives (in the case of akido classes). For me I treat it as a way of training the different ways of attacking to widen my array of knowledge and experiances.
Making sure that you hit to target is the next big thing, never aim off to the side or short of the target. Dont knock your partner out! but if your moving fast or slow, training easy or hard, always ALWAYS hit to target.
The last thing to think about is to learn how to fall safely and know how to react naturally (head moving back if you get punched in the head). Then to take the two and make them one, making your martial movement natural and your natural movement martial.