This review may contain spoilers. I can handle the truth.
It has it's problems, mostly in tone, but it's focused enough on its characters to compensate. Absurdly hilarious.
There's a part where after Robin Williams' son, Kyle, kills himself one of Kyle's friends tells Williams he doesn't understand because Kyle just "didn't seem that sad." This would have been sad just in the context of the movie. It was much more sad.