Without such an amazing cast, this would have been pretty lackluster. Definitely not the best movie of the year, but worth watching on DVD.
There is an amazing bit of meta comedy in this where George Cloony explains to Ewan McGregor what it means to be a Jedi knight. However, aside from some amazing casting choices including Jeff Bridges essentially reprising his role from The Big Lebowski and Kevin Spacey playing a sociopathic psychic, the film never really fulfills its comedic potential. There are some hints of a criticism of the excesses of military intelligence and the whole thing plays like a condemnation of the Iraq war, but neither of these things is fleshed out in a satisfactory manner. Still, I'd recommend seeing this on DVD (or on student discount Thursdays), if for nothing else than for George Cloony's impeccable comic timing.