Aside from the semantics one thing I have noticed that Aikido generally is much more accomodating to the individual. Without too much effort you can find a dojo which allows you to participate without too much effort.
In some dojos you are driven as much as the most gung ho karate dojo - in others the choice is completely up to you. Even in my own we have the full gauntlet from "I want to be a professional Aikidoist" to 40 year old housewife that wants to sweat "just a little bit" once a week.
The great thing is that it all fits.
No Aikido is not the lazy mans art but it can be an art for the more lzay to practice.
By my definition lazy means watching TV with a bag of corn chips. Anybody who gets out and does something, anything, is not lazy.