Animation World Network has a behind-the-scenes video on Disney’s computer-animated feature film A Christmas Carol (directed by Robert Zemeckis) which features scene previews and interviews with the movie’s celebrity voices Jim Carrey and Colin Firth.
Firth voices Scrooge’s nephew Fred, and Carrey supplies voices for 8 characters in the film, including Scrooge and the Ghosts of Christmas Past, Present and Future. Other members of the voice cast include Gary Oldman, Robin Wright Penn, Bob Hoskins, Daryl Sabara, Molly C. Quinn, and IMDb.com also lists Cary Elwes and Michael J. Fox as lending their voice talents to the film although this has not been officially confirmed as of this writing.
[Thanks to Doreen for the heads-up.]