For those interested in Laserdisc preservation progress, read on.
Currently, the Domesday Duplicator hardware itself is stable, and has been since around September of last year. The designs, schematics, and firmware are available for anyone to download and build themselves, who wants to start capturing their own discs.
Meanwhile, focus has shifted towards improving the output of ld-decode, which generates an uncompressed video output from a capture file produced by the Domesday Duplicator hardware. This is the primary reason why there hasn't been much if any movement on the MAME front towards adding LD games quite yet: We'd like the output of ld-decode to be largely stable before starting to add a lot of LD captures. People already get cranky when they have to re-download ROM sets that are a few kilobytes to a few megabytes in size - the amount of wailing and gnashing of teeth would be astronomical if we forced people to redownload upwards of 100 CHDs the size of Cube Quest each time there's a major improvement in the output quality of ld-decode.
For those who want a demonstration of the current capabilities of ld-decode, here's a promo video that was released a couple weeks ago to mark the release of ld-decode rev4:
As an aside, it appears that ld-decode is at least partially capable of decoding raw RF captures from a VHS tape, given appropriate adjustment of the decoding parameters:
Similarly, there's also another person working on getting ld-decode to be able to decode the output of the "HackRF" project, which is a SDR (Software-Defined Radio) capable of broadcasting and receiving analog television signals:
The plan is for rev5 to be released on the 28th of this month (February 2019). Among other major improvements, it will hopefully contain EFM demodulation, which will allow for decoding the data contained in the Domesday discs, as well as support for decoding digital audio and AC3 audio on laserdiscs which used them.
Anyway, that about wraps up this update. I'll be replying with any other interesting screenshots that pop up in the #domesday86 channel on Freenode.