Jack at DSNY posted a video a few weeks ago showing a new ride system oddly similar to what is shown in Brazil. With the ride system from Dynamic Attractions. shown at the 16:28 mark
One of the aspects of the ride is that it's supposed to be a rally race, not just a vehicle going off roading, and one of the features of this system is that it will allow the vehicles to take slightly different paths that may cross throughout the course of the "race", something that wouldn't be possible with the slot car system.