Do you have a source for a release list? Cuz I don’t.
The best I can think of is to look at Index: if-archive/infocom/patches , which is old (1999) and therefore probably doesn’t include any development versions. But it does includes hacks and betas.
No. I was thinking it wouldn’t be too hard to start with everything marked unknown and as multiple people confirm a particular version being present on original commercially available disks, they’d be identified as released. There aren’t really that many versions and there are a lot of collectors with original hardware. 
I’ve updated The Obsessively Complete Infocom Catalog to show the recommended version in boldface.
The bold selections seem pretty cromulent, but the Sherlock choice surprises me.
- sherlock-dev-r97-s871026.z5 – Appears to be mid-development; the trademark and subtitle are not yet set.
- sherlock-nosound-r21-s871214.z5 – Masterpieces version, PC.
- sherlock-r22-s880112.z5
- sherlock-r26-s880127.z5 – Masterpieces version, Mac.
- sherlock-nosound-r4-s880324.z5 – Final-dev.
I would recommend the version with sound, identified here as “Masterpieces version, Mac.”
The same can probably be said about The Lurking Horror, though I’m not sure which of the Amiga versions should be the recommended one if so. The Infocom Fact Sheet says 219 was the one included with The Lost Treasures of Infocom, but the changes between that and 221 seem small and apparently 221 was an official release?
And then we have the graphical games. At the very leash Journey looks different depending on what platform you tell it it’s running on. I don’t know if any interpreter runs the Apple II mode correctly, but here’s SDL Frotz running the Mac version.
The Amiga version. (Almost the same as as the Mac version, but on the Mac the title of the game would have been part of the window title. Apparently on the Amiga it had to draw that title by itself.)
And the DOS version. No line-drawing characters, apparently, and no game title.
The DOS version is the final one, and in theory it should be able to run all three of these modes depending on how the interpreter introduces itself. In practice, I remember running the DOS version as Amiga caused some minor glitches partway through the game.
Oh, yeah… Lurking Horror Masterpieces version r203 doesn’t have sound. Both r219 and r221 have sound.
Infocom Frotz is using r221.
I switched it to lurkinghorror-r219-s870912.z3 and sherlock-r26-s880127.z5.
For the v6 games, I’m just not going to recommend a version. Boldface is withdrawn. Getting them to work with all resources is more trouble than the v3/4/5 games, and I haven’t done it myself, so I’m not willing to make official-looking recommedations about it.
Spatterlight does its best. Apple II mode is very similar to DOS mode, except that it removes some spacing around the borders in order to fit all the menu text.
The Infocom Fact Sheet is pretty clear about the release status in its Datafiles section: everything that is not marked otherwise is a released version.
It’s clear but I have a sneaking suspicion that PDD is looking at the same information that I am.
Is he working from a known list of releases, or did he look at the same file collection and assume that the last one was a development repo? Because that’s what I did.
