At the University of Arizona, there is a Masters degree offered in the study of Piano and Dance Accompanying (page 11). Suzanne Knosp is the head of that degree - she is a great pianist, with a wide knowledge and love of dance. I studied dance accompaniment with her for one semester, before I traipsed off to CA.
Shenandoah University offers a Masters degree in Dance Accompanying, also.
There is also an International Guild of Musicians in Dance, if you are curious about the career choice and would like some contacts in the field.