Well, it was, ok. I think the theory of too many great actors spoil the soup applies in this case.
With so many characters in this film, I will comment on the big ones:
Brad Pitt - spacey, adorable, slightly feminine, curious (loved him)
Frances McDormand - hopeful, shrewd, also adorable
Malkovich - elitist, scary, crazy, classic Malkovich
Tilda Swinton - icy, direct, also scary, funny in the not meaning to be way
Clooney - pathetic, weasel, ass, jerk (oh, I hated him)
This was one of those movies like Snatch or Lock Stock with a ton of characters all wrapped up in each other's lives where it comes together at the end. Except not nearly as good. Rent this one.