Just came back from the movie I, Robot. I have to say this as I have read the original book extensively and I really credited Isaac Asimov for creating 3 simple robotic rules but yet, it could create complex and chaotic behavior. The book itself revolves around a collection of stories but usually it centrals around Dr. Susan Calvin - the robo-psychologist, Gregory Powell & Michael Donovan - both are onsite technician to troubleshoot for problematic robots, Alfred Lanning - the director of United States Robot & Mechanical Man Corporation. The movie however centralized an additional character, which is Del Spooner (Will Smith).

However, I'll skip the whole thing and list out the differences between the book and the movie. It should be easier for someone to either has read the book or watched the movie.

• No Del Spooner character in the book.
• Greg Powell & Michael Donovan's funny interaction has been removed.
• There's only NS-2 model in the book, not NS-4 & NS-5.
• Alfred Lanning didn't commit suicide in the book.
• Robertson's character was only mention for being the founder of USR.
• There are no two-positronic brain robot in the book. The nearest to this is a modified NS-2 robot that was constructed with the First Law: "A robot may not injure a human being, or, through inaction, allow a human being come to harm." The modified version has the First Law changed to: "A robot may not directly injure a human being." This has cause the robot's inaction to lead to some questionable ethics.
• The Robot Brain was actually a very child-like personality with extremely effective at solving problem, as long it doesn't contradict the First Law. In the movie it shows the Brain, also known as VIKI to evolve beyond comprehension to base it's behavior to the First Law
• Book shows that the 3 Robot Laws is unbreakable even beyond evolution. The movie shows the 3 Laws can be broken if the positronic brain evolved beyond it's own capacity.
• Nanites were not featured in the book. But then again, the nanotechnology wasn't known widely during 1950s.
  

There, I guess that's the major list. Oh, did I mention that Gene Roddenberry, the creator of Star Trek: The Next Generation begged Isaac Asimov to feature his robotic rules & positronic brain? Isaac strike a bargain with Gene and allowed him only to use the idea of positronic brain, but never the Robotic Law. That's why positronic brain was mentioned when Georgi troubleshooted on Data's circuitry.

It's a great movie, coupled with a very one-liner joke. I saw some complaints on the movie, but heck if they have read through the book first, then most of them should have see the movie in a different perspective. Like I said, always RTFM.