This is great stuff Amag. I was going to suggest that instead of using different icons, you could try replacing them with 3D objects (see the attachment).

In order to correctly orientate the bus (and geometry), you'd need to do some tracking of GPS coordinate from moment to moment to get a direction, and then a rotation in lat/lon space (remeber that it's scaled by cos(lat) in longitude - i.e. longitude gets squashed closer to the poles).

This might take a little work but the results would be very impressive and a great example that we could share with other people.