This discussion says that it's not the meetings, it's what we do with them:

If the meeting is focused on making a strategic decision, we spend as much as ten hours of design time for every hour of meeting time. We want people to think together, not just listen to reports or information that could have been distributed in other ways. Getting people together is expensive, too expensive not to engage their best thinking around important issues. We focus most of our thinking meetings at the strategy level with just enough content presentation to make sure people have a firm grasp on the elements of the issue. This means giving people information prior to the meeting and providing content that has been boiled down to the bare essentials. It means developing visual representations and prototypes of the information so that people can interact with it on different levels. It also means understanding that most strategies fail and deliberately looking for alternatives.

...via Patrick Mayfield