The Invention of Lying is a nice enough idea, and has a nice enough cast, (fantastic, actually,) but it's so offensive that... well, to put it nicely... I kinda hate this movie.
The one and only complaint about the acting I have regards Jennifer Garner, who I usually like. In this she played her super shallow character as... well... super shallow. I could not, for the life of me, figure out why anyone would want to be around her.
It was an interesting movie, but dull and obnoxious. I suggest you do what I did up until a few days ago, and PASS on it.