I think it depends both on where you are and what denomination you're part of. In Texas, the mainline denominations (Methodist, Presbyterian, Episcopal, etc.) seem to be in decline, but non-denominational churches are growing at a healthy pace. Even the Catholic Church here seems to have made something of a turnaround, with growth in my diocese such that they just created a new parish to take pressure off some of the overcrowded ones. Admittedly, some of that growth is from immigrants moving here from Latin America and Africa (especially Ghana for the Catholic churches), but it is growth nonetheless.