What's effective is how matter-of-fact "Fair Game" is. This isn't a lathering, angry attack picture. Wilson and Plame are both seen as loyal government employees, not particularly political until they discover the wrong information.
Ty Burr (the Boston Globe):
‘Fair Game’’ takes one of the more shameful sub-chapters in modern US politics . . . and turns it into a strident, condescending Hollywood melodrama. It’s one of those nobly intended affairs in which Important Stars explain to us how we’ve been screwed by our elected representatives.
I'm mostly with Ebert, although Burr has a point about the final scene with Sean Penn's Joe Wilson, which I'm sure is verbatim from one of Wilson's speeches, but plays too neatly in the context of the film. Most of the film, and the parts that work best, show Naomi Watts's Valerie quietly and intensely doing her job -- developing "assets", analyzing information, reporting her findings, exchanging insights with other agents. The same applies to Penn's portrayal of Wilson when he's asked to check out reports of a sale by Niger (a country he knows well) of yellowcake uranium to Iraq. But Penn gets Wilson's blustery, combative side right off the bat, and you can see right away what's going to happen when Wilson discovers that his conclusions have been ignored (he determined there was no way any such sale could have happened and was ultimately proved right).
Director Doug Liman shot the film in a kind of casually intimate style -- not exacty documentary, but more like you just happen to be nearby while various events are taking place, whether they're political, covert or domestic. A ripple of recognition went through the audience at the screening I attended when David Andrews' Scooter Libby showed up at CIA HQ. Given how events subsequently played out, it was pretty clear who was going to be the film's main villain.