I don't remember that it was a separate thread but I do remember you bringing it up and I think it has great potential.
To be great for reading would take a lot of thought about the symbolism in the cards so there would be a lot of work that way, too. For example, would you want the second view to show the continuation from the original view (what happens next) or the + and - aspects of each card, or the images as "unconsciousness brought to consciousness" or....? I think there would have to be a real "theory" behind it, to make it coherent.
ETA: Maybe this thread:
http://www.tarotforum.net/showthread.php?t=51158
Thanks for taking the time looking for the thread, The link you provided does also touch on the subject to a degree certainly, but the thread I was trying to recall was more specifically about lenticular cards.
Nevertheless, the idea of incorporating the visual illusion of animation and dimension does indeed have incredible potential, and on various levels. Lenticular can produce a simulation of movement, not just a first and second view. But even that may now be redundant with newer technology. The wafer thin cards that I mentioned in the link you provided don't seem quite so far fetched in this new world of iPad tablets. Which in turn will become increasingly thinner and physically flexible/pliable. One can see where this might lead.
Your concepts of "the second view to show the continuation from the original view (what happens next) or the + and - aspects of each card, or the images as "unconsciousness brought to consciousness" or....?" are certainly potential ways to go. I also envisioned many cards demonstrating a "situation+action=consequence" scenario.
But Tarot isn't just about delivery, its about content. As you point out any such future direction would require a lot of thought regarding symbolism to do it and the potential of the new medium justice. Otherwise yes, like so many things in tarot of late, it could be just a cheesy novelty. It would also require a truly immense amount of physical work in preparing multiple levels of each image. I for one no longer feel I would have the energy or enthusiasm for such a commitment, along the dubious reception it might be met with, but I'm looking forward to see what others will eventually come up with.