I am hoping we are not seeing a clone of the stage musical in the movie musical, including a note-for-note comparison. I want to see a fresh perspective and a different cinematic vision.
Hugh is already bringing a different vibe to the movie version - he looked manly and noble, despite the dirt and grime and scars from years of imprisonment. If they adjust the key he sings in, maybe it is to make the musical score more accessible to the ears of the general movie-going public. Many people do not like movie musicals because the music ( especially if they think it is of operatic sounds) alienates them. But if the focus becomes the drama and less of how each note is sung, then maybe we can have the movie that will please a universal audience.
Also, someone I know who is a true fan of the theatre ( she is a regular on practically every show seen on Broadway) has made a comment re how a baritonal voice seems more in keeping with the persona of a gruff, strong-looking convict...and I thought that was probably the reason why Valjean in the original French concept album was written for and sung as a baritone.
But it is early days to argue about how the actors are singing the songs
We don't even know how this stolen scene from filming will wind up in the movie. I want to be surprised to some extent - so, hopefully, there won't be too much temptation by way of stolen scenes from the telephoto brigade.