Though marketed as a romantic comedy, the Vince Vaughn vehicle was conceived as anything but:
[A]ccording to the filmmakers, it’s not a romantic comedy. It’s not even an anti-romantic comedy. Rather, they designed the movie to explore, in comedic and dramatic tones, one couple’s breakup, when neither wants to move out of the condo they share. It’s akin to Woody Allen or even Neil LaBute territory, except that in this case it was Vaughn himself who mapped out the terrain.
The writers compare it to Annie Hall and Paper Moon. I think this can safely be put in the over-flowing file of wildly mis-marketed movies.