I've made visits there off and on since the mid-1950s, it's definitely a cool place. My only disappointment in recent times was that a stand of old growth hemlock in the section of the park below Rt. 118 appears to be in bad shape, dying off. That used to be the "Evergreen Cathedral" where you could walk on a thick soft carpet of needles and stare straight up at trees that seemed to go upward forever. The falls themselves, and the rocks surrounding them offer never ending possibilities.
Ganoga Falls (94 feet high), taken on Ektachrome (32) with my Argus C3 in 1959:
Scan of a 4x5 shot with B&J Press circa 1963:
35mm Plus-X in my A-1 in 2007:
More here and here, plus a few in the midst of WPPD 2007 endeavors.
That early fall looks as though it could be pretty hectic this year; I certainly couldn't commit this far ahead of time, but it could be of interest.
If you do the full trail, decent hiking shoes are highly recommended.