For folks like Datameister and I heh, who actively miss Haunted Mansion's normal state during the fall/winter months, or those who just like tidbits and odds and ends to look for...a partial list of the unchanged elements (both visually and soundtrack) during Haunted Mansion Holiday from the regular Haunted Mansion. If you see or know I missed, please do feel free to post with them and discuss..
1) The normal stretching room scream plays when the lights go out, even though the Jack audio is partially played over it, along with the crashing thud of the landing.
2) In the Corridor of Doors, the door animation and soundtrack of growling and laughter and screaming remains the same, as well as the portraits of various ghouls lining the walls.
3) In the ballroom, characters such as the birthday ghost, the old woman in rocking chair, the ghost above the fireplace, the banshees and chandelier ghosts, the duelists, the dancers and the organist all have their normal animations and locations.
4) The sound of the bride's heart beating can still be heard throughout the attic scene underneath the music.
5) In the cemetary, unchanged in location are the owls, cats, and the skeletal dog along with their soundtracks. The old man listening to the mummy keeps his same dialogue as well and no physical changes.
These are the main ones I can think of...there are of course figures and elements in the graveyard that get minimal changes, like putting the Santa hats on the pop-up ghosts and ribbons on the tombstones...but still is changed, as well as all the music/vocal tracks for the usual cemetary ghosts. Are there any elements I have forgotten?