Vince just isn't right for a Christmas movie...
... let alone two in a row! You need a certain sweetness in your approach to the holiday season, and he just doesn't have it. Like in the scene where he uses the snow globe and sees his girl have a 'meet cute' with a guy she's giving a ticket to, I assume you're meant to feel sorry for him, and then practically the next scene has him dancing and whooping it up with the elves?! One scene is a perfect fit for Vaughn, and the other isn't, leading to lots of ideas assembled in a way that don't merge very well into a cohesive whole.
I understand that the intention was to contrast his caustic frat-boy attitude with the more pure evocation of childhood innocence that Christmas represents. The issue is, Vince is neither as misanthropic as Thornton nor as carefree as personalities like Dudley Moore or Will Ferrell, so the tone of the film falls between two stools. Even worse, when the film moves away from the main character, the uneven treatment begins to affect the supporting cast as well. It becomes almost boring and bureaucratic at points, specifically in its uninspired handling of the Spacey and Giamatti characters.
Everybody has to restrain their usual personality in order to fit into the basic template of what feelgood seasonal entertainment is thought to be; whether it be Saint Nick switching from paragon of virtue to snowball fighter at immediate requirement, or Clyde suddenly joining the good guys because he gets his Superman cape (since Spacey was channelling Lex Luthor again for the whole time, it wasn't hard to see that one coming... ) it all felt cloying and schmaltzy and not true to the performers own instincts. Why hire people if you expect them to subdue what they're naturally good at?! Weisz, Richardson and Banks fare no better, either. Each lady is a talented individual in their own right, but they're also given virtually nothing to do.
As a result, despite a first rate cast, this is a movie that I'm afraid doesn't deliver much in the way of glad tidings or good cheer.
It's made from bits of real panther, so you know it's good...