Digital Dash

With all the technology available to cars, why haven't they picked up on LCD displays yet for dashboards, or arguably even better, TFT. (see the OLPC project for what could be perfect, as it can be both backlit and ambient lit)

True digital displays open up a world of possibilities, including additional on-dash display of the speed limit, and should speedlimit indicators be machine readable (from embedded wireless in the roads, to OCD signs), that limit can be displayed on the dash alongside current speed.

I have heard it argued that the speedo should recalibrate so that the limit is always top center - but I think this is poor as it breaks the existing spacial memory of the speedo dial.

epaper could be neat also, since in case of catastrophic failure (say, crash), a recovered dial could give an idea of speed/conditions moments before the crash...