I'm often asked by leaders planning conferences, meetings, symposia (there's that word again), how to solve a dilemma: on the one hand, they want to make sure people leave with concrete takeaways, nuts and bolts solutions that attendees can execute when they get back to the office. On the other, they want to engage attendees in significant conversation (see Sue Pelletier's comment) that leads to new thinking, innovation (as Jeff De Cagna talks about) even transformation. They're afraid if they focus on the latter, people will feel it's going to be too "touchy-feely" and "precious" as opposed to, well, useful.
Truth is, you need both. But without engagement, in which attendees interactively participate in shaping the experience, it'll be just another conference, hardly memorable. And the leader certainly won't feel like an agent of change.
My advice is to get attendees focused before they arrive at the gathering. Ask them several questions that assure them there will be practical outcomes but include several queries that get them thinking about the significant issues you want them to wrestle with when they get there. If you've done it right, they'll be curious as to how others replied, and will expect you to provide the forum in which those issues will be addressed openly.