If you're one of those people that would rather pluck out your eyes that watch a Will Ferrell movie then I'd like to say you'd be making a mistake in this case. Ferrell plays his IRS Agent character at a very low key. There's no running around in his underwear, no yelling and very little to connect him to his established drunken frat boy screen persona.
Couple that with some very good direction, a smart script utilizing some very dry humor and some excellent performances by Dustin Hoffman, Emma Thompson and Queen Latifah and you get a pretty damn* good movie.
(*by virtue of this being a "liberal" blog I am obligated to swear regularly)