I guess most of us just assume that large churches have contemporary worship, but that’s not always been true. Many have grown with traditional worship styles. However, very few continue to be traditional.
What was a strong preference in 2000 is virtual unanimity in 2008. Nearly all megachurches have contemporary instruments.
Why? Plainly because this is the culture of the people being converted. There won’t be many new converts who play organ or choir music on their mp3 players! They may like country or rock or pop music, but it’ll have drums and guitars.
It’s elementary mission theory that a missionary church adapts to the local culture, rather seeking to convert people both to Jesus and to the culture of the missionaries.