Here's an amazing interview with Louie Giglio about the Passion conference. The quote that just brings it all together:

But when you wed any expressions of worship and the teaching of God’s Word, the truth is what sets you free, not the music. Music makes you feel good, but the truth is what sets you free. When you put those two things together and you add to them a call to action, then I think you’re finding a sweet spot for what worship is.

If the call to action is not there, then we’re just soaking up a great experience, and man, give me more, more, more, more. We are consuming worship. The point of worship, though, as far as I can tell from reading the Bible cover to cover, is not for people to consume the worship, but for people to be consumed in the worship for the glory of God.

The combination of worship in music, strong theological teaching and then the call to action. Sweet! Take out any of those three and what you've got is a hollow reflection.