EDIT: You can view the official trailer here:
http://amostwonderfultime.ning.com/video/jim-carrey-a-christmas-carol
Looks like Jim Carrey will not only play Ebenezer Scrooge in the 2009 adaption of the Charles Dickens classic A Christmas Carol but he'll also be playing the ghost of Christmas past, present, and future.

From
Variety
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Jim Carrey will play Ebenezer Scrooge plus the three ghosts that haunt him in "A Christmas Carol," an adaptation of the Charles Dickens tale that Robert Zemeckis wrote and will direct for Walt Disney Pictures.
Zemeckis, Jack Rapke and Steve Starkey will produce through ImageMovers Digital. The trio recently made an overall Disney deal for their ImageMovers banner.
Zemeckis will shoot the film using "performance capture/Disney digital 3-D" animation, a continuing evolution of techniques he introduced in "Polar Express" and continues with "Beowulf," the upcoming film that stars Angelina Jolie.
"A Christmas Carol" will feature a touch of live action and computer graphics, the latter of which ImageMovers employed in the Gil Kenan-directed "Monster House."
The technology provides a playground for the chameleon-like Carrey, who will act the character of Scrooge through the periods of his life, as well as the ghosts of Christmas past, present and future. Zemeckis wrote the script specifically with Carrey in mind, and the actor said yes straight away.
It"s the second iconic holiday role for Carrey, who played the title character in the Ron Howard-directed "Dr. Seuss" How the Grinch Stole Christmas."
Bob Hoskins has blabbed to the Internet that he would also be in "A Christmas Carol," inadvertently revealing a project that ImageMovers had been trying to keep secret. While Hoskins -- who starred for Zemeckis in "Who Framed Roger Rabbit" -- might end up in the film, the studio denied that any deal had yet been made with him.
"A Christmas Carol" becomes one of several high-profile projects for Carrey, who hasn"t determined which he"ll make next, or how many he'll be able to complete by next summer, when studios are bracing for possible labor stoppage.