This article from CleanTechnica gathers more evidence supporting the theory that the ≡ will be equipped with a Heads Up Display.
I find HUD interesting and Tesla could implement it at a later date if feasible. Given their accelerated schedule, I would stick with proven dash tech but make it compact. HUD just adds another tech and manufacturing risk.
I suspect (guess) they are already quite far down this road -- evidence the plain jane dash in the prototypes, and the hiring of a HUD specialist. EM would see the advantages of having a totally programmable UI. Plus it would make the Autopilot much easier to use. It could overlay the AP information directly over the surrounding vehicles for example.
HUD is proven. It been around for over 4 decades.
It is easier to install. It is not a manufacturing risk. It is manufacturing simplification.
Looking at the prototypes, installing a conventional instrument cluster would require re-engineering.
What I suspect is that HUD has already been decided to be put in, but all the features that Elon and TESLA want it to do have not been completed because of the accelerated timetable for manufacturing and delivery. So, in true TESLA fashion, they will probably release the car with basic HUD software that pretty much comes standard like MPH, temp, etc and then update it in the future for things like autopilot.
Think of it this way, Tesla is as much a software company as a hardware company. Why is that so valuable, Apple figured this out long ago with the iPhone. Get rid of as much hardware in the user interface as possible, then you have just a screen which is a blank slate with which to design. A HUD is just another screen. If the Model 3 just has a HUD and its central dash screen, Tesla can introduce any user experience, feature or fix simply and instantly over the air. Also a HUD is even less hardware than an LED screen, so it both improves user experience while reducing costs. Brilliant in the concept's simplicity.
A well designed HUD would have a spaceship feel. Hmmm...
Another thread made the point that the central dash screen could also be a place marker for a rear projected DLP panel, (appearing like glass when off) further reducing cost and complexity by integrating both HUD and central displays into one module.
I think when EM alluded to it being like a spaceship, he meant it. Other cars will feel like antiques.