Professor James K.A. Smith has written a succinct open letter that expresses the practical problems with most of contemporary worship in evangelical churches, which can be seen here. An excerpt:
Dear Praise Band,
I so appreciate your willingness and desire to offer up your gifts to God in worship. I appreciate your devotion and celebrate your faithfulness--schlepping to church early, Sunday after Sunday, making time for practice mid-week, learning and writing new songs, and so much more. Like those skilled artists and artisans that God used to create the tabernacle (Exodus 36), you are willing to put your artistic gifts in service to the Triune God.