Ask any evangelical about the essence of worship and you are bound to get a wide variety of answers ranging from the musical style, to the use of big screens, to preachers who lay it on thick, to encounters with the presence of God.
Ask Terry Johnson, pastor of Independent Presbyterian Church of Savannah, Georgia and you will get an entirely different answer. He argues that worship is to be governed by God's Word (no surprise to those familiar with the 'regulative principle of worship'). Beyond that he argues that God's Word (not the pastor, not the band or the music, not the congregation) is to be front and center. Specifically, "God's Word should be read, preached, prayed, and sung." Beyond that the sacraments are important because "the are the word made visible" (Augustine). Using that measurement, how does your worship service stack up?
For those wanting to understand what historic, reformed worship ought to look like you need to listen to this interview: Office Hours: Terry Johnson on Worship. Listen and compare what is discussed to what happens in your house of worship. It reminds me of what was articulated in the book and DVD, Christless Christianity.