Researchers from MIT AgeLab and a typeface design company have investigated, how font readability of digital menus on a 7 inch display affects glance times of drivers, that is the time the drivers had their eyes on the display rather than on the (simulated!) road. Glance times were measured using an eye-tracking system. The experiment employed the following two fonts:

With 82 participants at various ages it was found that glance time for the lower font in above depiction was reduced by about 10% for men, but not at all for women. (One of the researchers hypothesises that may have to do with how women process information or interact with the technology used in the experiment).
Depending on the speed those 10% may make a significant difference in an actual dangerous traffic scenario. Hopefully, the car manufacturers see enough branding and emotional potential in super-legible fonts.
Related and worth checking out: Some weeks ago infovis experts have discussed speedometer design here and here.
(via Popsci)