So it seems that PUMA has beat me to it. However, their bot seems to run with an array of light sensors, so it's really just a high-performance line following robot.

I want to do something better. I want to build a system that can be easily modified for any track. I want to build something cheaper, and open source.

Challenge accepted, PUMA. Challenge accepted.

I also did more research into these types of builds, and it looks like I can get some type of Sensored Brushless motor that I can use in tandem with the ESC to tell how fast the car is traveling at all times. I would use the steering servo with this to do some kind of rudimentary integration based on a curve offset. Here's a great article that I think will be the key to unlocking the kind of behavior I'm looking for: