This is
not just speculation. Have you looked at the (filed by A123 in their poaching complaint) A123 vs Apple court documents? Have you looked at the car/battery/mechanical engineers (LinkedIn sources, people moving to Apple) hirings reported by 9to5Mac? Have you looked at the documents uncovered by the Guardian involving US officials (access to car test tracks etc.)?
Either you think all these publications got it completely wrong or a few hundred (soon 1800 according to the WSJ) car and battery experts at Apple just play poker indoors in their secret location or enjoy the beaches in California doing nothing...
Apple doesn't show stuff in progress or concepts. If they continue their usual modus operandi with the car project:
Ignoring all leaks (and there will be leaks, hard to hide a car in testing phases...), they will likely send out a PR invitation one day and...boom...the car or whatever mobility initiative they are working on will be shown off
close to the actual release.
PS: Of course they could still stop the project betwen now and 2020. But moving to close to 2000 people means the project already took several hurdles along the way (maybe even got accelerated according to the latest WSJ article).
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There never were credible rumors for a TV with a screen moving into production.
The TV rumor was propagated by AAPL analysts with a mediocre track record (Munster et al.), later also based on one quote by biographer
Isaacson (who didn't get a lot of technical details right in his SJ biography, not a good source).
Same for hirings linked to TVs, there never was credible evidence beyond mere R&D TV lab concepts. Wearables (now we already have the Watch on sale, the first item in the space from Apple) and the car project are different:
Many sources including paid financial publications with more careful track records/checking, LinkedIn confirmation (hirings by Apple) and additional reports by bloggers with a good track record on all things Apple.