Since the "Once Upon a Dream" Halloween Villains' Nightmare Layover is getting some good comments, I'll start the Christmas Layover, titled the "Once Upon a Christmas Parade".
To be excused from the winter holiday layover will be Dreams of Power (the villains' float) and Dreams of Adventure (Jungle Book/Lion King); however, characters from those films will be following the Big Eight (Mickey, Minnie, Donald, Daisy, Goofy, Pluto and Chip 'N' Dale). For this event, there will be new lyrics to the title song, retitled "It's Just Like Christmas" for the event, and is in the proposed Halloween Layover, there will be no show stops or scents coming from the floats.
The layover will be a Christmas/Winter theme; think giant marching Christmas tree, ice skating rink, etc. The opening float remains the same, but with a "Once Upon a Christmas" sign, and the Big Eight wearing Christmas-themed outfits (Victorian Era like Mickey's Christmas Carol). This would be followed by the Rocking Float Horse and Toy Soldier band (Yes, it would be a band, not a marching unit.)
Laughter and Fun is followed by a hugenormous - is there such a word as "hugenormous"? - rolling Christmas Tree, then Friendship, Fantasy, Romance (with Ariel now in her human form and Tiana replacing her in the front for 2009, and in 2010, Rapunzel on the swing as Jasmine moves to the second part with Ariel) and last but not least, Father Christmas/Pere Noel/Santa Claus. Dancers would adjoin the floats in all cases like Gingerbread Cookies, snowflakes and such. To top it all off, it's going to snow (via snow machines) through the parade route when Santa arrives.
There you have it. Likes, dislikes? Better ideas? Feel free to post them!