Differences between the serial and the film
Having now seen both, I thought it would be fun to try to list elements of the serial that were changed in the film. Because, aside from the blindingly obvious (they drive on the other side of the road!), there really isn't all that much that was changed. Plenty had to be cut, to get from 6 hours down to 2, but not a whole lot was altogether changed.
So try to leave out the blindingly obvious and what was cut altogether, and let's see what we can come up with :) Posting this on the message boards for both the serial and the film.
And, of course, there are spoilers in this post.
Della's last name and status: In the film, Della Frye is a rookie "cub" reporter with very little experience in actual journalism (she's a blogger). In the serial, Della Smith, though clearly several years younger than Cal, is essentially a peer.
The boss: This isn't what I meant by blindingly obvious :P I meant the steps taken to Americanize the story. Anyway, in the serial, the newspaper editor is Cameron Foster, a man. In the film, it is Cameron Lynne, a woman.
Cal and Stephen's relationship: In the serial, Cal is Stephen's former campaign manager. In the film, they are simply longtime friends (and college roommates).
Cal and Anne's relationship: In the serial, Cal and Anne are scarcely acquainted at the beginning, but go on to carry on with an affair. In the film, they are former lovers who remained friends.
The briefcase thieves: In the serial, the male briefcase thief is named Kelvin Stagg, and the female is never named. In the film, the male thief is named DeShaun Stagg, and the female is named Mandi Brokaw. She is also revealed to have died offscreen at some point (no such indication in the serial).
The evil corporation at the heart of it all: In the serial, the big baddies are an oil company. In the film, it's a Blackwater-esque private militia company. Stephen Collins' committee job within the government is tailored accordingly.
The assassin and the climax: In the film, the showdown with Robert Bingham is the climax, with the reveal of Stephen Collins' complicity more of a twist ending. In the serial, Bingham is killed about two-thirds of the way into the story, and Cal's confrontation of Stephen carries much greater tension.
And that's about all I can think of. Anybody got any others?