I play for a methodist church and hymns are part of the liturgy each week. We follow the liturgical calendar (Epiphany, Lent, etc...) in choosing the hymns. We normally have a morning hymn, sermonic hymn, then an invitational hymn. In addition to that, we use many hymns in the unchanging liturgy like Old 100th, Gloria Patri, and the like. We have however found a wonderful mix of traditional and contemporary. Depending on the choir, they'll sing either gospel, traditional, or contemporary music.
I think it's very important to be exposed to all of these types of music. Everyone has their favorite, but if we aren't cognizant of the old hymns, how can we ever get a full idea of what praise through music is. I think the big reason why contemporary seems to be winning the battle is because it's easier to play. 95% of gospel songs coming out these days consists of the same basic chord progressions. If you open up a hymnal, you'll see the text uses a greater number of words than what contemporary music consists of today. As well, the music is, harmonically, much more invovled than the contemporary gospel song. Hymns aren't easy to play, nor are they easy to sing. It takes time to learn how to play hymns well. That perhaps is the big reason they're falling out of use....
My two cents.