Recently I read a terrific article in Renew.org by Joel Singleton.
4 Tracks in American Christianity: A Tool for Cutting Through the Smoke and Heat
I highly suggest you read it, as I’m going to take this post to talk about it.
Singleton puts forward a basic way of understanding the difference in church philosophies in America, and he cautions that this is just a tool for understanding, not a surefire way to just group churches into categories.

(the above image is supplied by Renew.org)