Just came from the show and I can say that it's worth the visit. There are two shows of photographs running concurrently.
Gershwin to Gillespie, mislabeled as a show or rare books and maps on the website, is actually a great set of portraits of folks from the world of music, from a Steiglitz shot (of a composer who's name I immediately forgot) through wonderful jazz age images to Annie Leibovitz closeups of Dylan.
Picturing What Matters, a collection of images from the Eastman House archives is put together by the staff of that museum - as often members of the business office or shipping department as curatorial staff- contains a broad range of pictures both well known and obscure, from mid 1800's to very recent times. Interesting stuff and well displayed. Go see it!