There is definitely a difference in the types of actions that are available between the two components.
As far as I can see, rulesets offer actions of a greater scope than triggered rules alone, but triggered rules seem to pick up on and allow me to use form actions as launch points for conditions and actions. It also looks like Rulesets can be "embedded" almost like subroutines in larger rulesets.
However, I am curious. Can someone give me an idea of where and why you would use a ruleset vs. a triggered rule?
Thanks very much,