I´ve checked some (not all though) of the videos and sounds of Tomorrow on this site and it seems to me that the key´s differ about a "half tone". Mary K Lombardi, Sarah Jessica Parker, Rosanne Sorrentino, Marissa O´Donnell and Brittny Kissinger are all in the same key (F), but I think that Andrea McArdle, Alyson Kirk and Kirsti Coombs sings it a half tone higher (in F#). Marissa o´Donnell sings it in F in the 30th Anniv. recording, and so does Brittny in the video from the Tony´s. This is just a quick check with a tuning-fork, not a piano so I could be wrong though.
I have not checked the keys for the two recent Annies, Amanda Balon and Tianna Stevens.
But it was fun listening to all theese Tomorrows again! All theese girls sings it so well, they are all different, but wonderful.