Bit of a disappointment this one, from the trailer and what I had read about it I imagined that this would be funnier.
While the finished product was moving and funny to a point I didn't buy into Carrell and Knightley's relationship during the film. It just seemed a bit creepy to me, from their first meeting through a window to the end product.
A pointless cameo from William Petersen and an under used one from Martin Sheen just didn't make sense.

Overall there is nothing about this film that sets it apart from others and nothing about the leads performances that merits any special mentions.