Whenever you steal a police car in GTA IV, you're getting more than just a new paint job, flashing lights and access to dull "Vigilante" missions. You'll get access to the police crime computer, which among other things enables you to search the LCPD's criminal database (it also enables you to call for police backup, although Rockstar wouldn't tell us what that meant). In this case, Niko typed "Rivas" into the computer and - after a brief search - got back two profiles, one of which was Lyle's. The dossier gave us Rivas' photo, and more importantly, the address of his hangout.

Hitting the button marked "Locate" immediately drew a yellow, GPS-plotted path to Rivas' doorstep on our onscreen map. The Rockstar reps took this opportunity to tell us that the GPS system will vary a little from car to car, with some of the nicer rides featuring accurate voice navigation. The idea of hearing "turn right ahead" instead of constantly having to eyeball a map sounds cool, although you'll be able to turn it off if it isn't.

When Niko arrived at Rivas' house, the little weasel lit out through his bathroom window and fled in a car - and, thanks to a bug, he immediately escaped. This failure prompted Niko to call Brucie, who - while furious - told Niko to come back to the garage, at which point the opening cutscene would have replayed (with slightly different dialogue) and the mission would have restarted.

Interestingly, this failure revealed another cool feature in GTA IV - you no longer have to backtrack after you've failed a mission. Instead, Niko can simply choose to restart it via his cell phone, at which point the game will automatically drop you back at square one.

MR: What's the verdict on the crime computer? Is it an awesome addition that adds depth to the world, or just one more complicated distraction from driving and shooting?
CB: Well, that distraction only appears if you get in a cop car.
MC: I thought it added an interesting twist to another 'kill informant' mission.
CB: I love that cop cars aren't just "click right thumbstick to trigger Vigilante" now.
MC: did two guys appear on the in-car computer in your demo?
MR: Yes, because the guy who was giving the demo just typed in "Rivas" instead of "Lyle Rivas"
CB: I wanted to ask what would happen if we chose the other guy.Do you think players can just skim through the crime computer on a lazy day, chasing down whomever they find in the records?
MR: Probably it'd show you where he lived, and then nothing would happen because there'd be no marker to trigger the misison.That could be fun - "vigilante" taken to another level - but it'd also mess up the flow of the missions, so probably not. Or if so, there'd have to be restrictions.
CB: I wonder what kind of extra depth has been given to other specific vehicles, like ambulances, fire engines, pizza scooters, etc... care to speculate and dream?
MR: Could there be a "pizza computer" that clues you in on the suspicious characters most deserving of pizza? One could dare to hope.