Good stuff Leon. A serious thought experiment on this topic has genuine merit, though it was fun bouncing off the topic for a bit there.
Fusion should be happening controllably, reliably, cleanly, and cheaply by then, and what can be done with that amount of energy is going to be interesting.
More nanotechnology in tire design for sure. We have no concept of traction if all we know is rubber and asphalt.
Mag-lev and practical superconducting applications should be well within technology of that time so the nanotech tires would just be a passing fancy.
Heads up display absolutely, or maybe something unimaginably exotic at this time but conceivable given current understanding and technology - mental imaging. Direct input into brain centers of perception and awareness would both overcome the dangerous distractions of controlling a vehicle moving at high velocity in crowded lanes, and also allow indulgence in those pleasurable distractions knowing you're still coupled to environmental concerns.
Spatial awareness enhancement through far broader views afforded by satellites and databases and sensors and data processing, which if coupled by accident avoidance technology that should be completely foolproof by then may cause the word "accident" to drop out of common usage. Redundant systems at both ends would also banish "failure" at least from concern.
Pollution won't even be an issue. There should be no step in the energy production process that results in any harm to the environment. However, what will be left of the environment well before those accomplishments occur is an open question - at least I pray it's open...
Frank
p.s. Oh yes, I used to love white cars and the ones I owned are still my favorites, but my heart has turned black, black and tan!