Is it just me, or would other people also like it if you were told WHAT the updates did/were. As maybe my game is running fine, and I don't want to re-download it to get a mystery update.

If you click on the game in the library you can see the button "More". Clicking on that there is the option "Changelog", telling you details about the update.

Nope. Not there. I click on more and these are the options.
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Which game are you talking about?

Many. I currently have 15 update notifications to some of my games. Little Blue dot tells me something has changed.

Adventures of Shuggy, Beneath a Steel Sky, Freespace, etc. None of them are showing anything ABOUT the updates.

Ah ok. I guess you have not been updating for a long time? Because the changelog was only introduced with the new account system. And in addition in the beginning of that feature there where tons of updates which did not change anything and just made the games supported by the galaxy client, so they got no changelogs.

Normally games now always have a changelog when something changes. Also everything is normally documented here in addition:
http://www.gog.com/forum/general/the_what_did_just_update_thread

It does not always seem to show, and when it does it is often miss leading. Like for Starpoint Gemini 2 the change log says "Patch 1.9001 (19 November 2015)" but I see no patch so I guess the whole installer has to be downloaded

But then there are a few possibly related display bugs like a few of the games I own do not show as owned when browsing. The witcher 3 DLC shows as being owned but not the main game. If I try to buy it a second time I do not get a warning.

The whole update thing could use an overhaul. No idea if it works with Galaxy but I do not use that.

cheers

Ok strange. I know about the bugs with games not being shown as owned (has something to do with different IDs because of preorder etc.) and of course often games do not get an update flag so you do not even know there is an update. But that the changelog is not showing? Never realised that.

Thank you for the link to "the_what_did_just_update_thread". I spent over half an hour for dubious results at checking within that thread what might have changed for the less than a dozen games I own on GoG. Not the most user friendly tool.

It is a pain to browse that thread as the search-within-the-thread field is somehow buggy (for instance, it highlights non relevant partial keywords in the text). Moreover, the change descriptions are often obscure (noticing an installer file size change does not say anything about the update itself), and a check against the purchase date is mandatory to see if what I have downloaded is pre or post update. No way to do it in an other way than by frantically swapping between web pages; looks like web 1.0.

What exactly do you want to do?

If your meaning is to keep all your GOG games downloaded and up to date, I suggest you look into gogrepo.py. With it is it very easy to keep your local GOG game collection up to date, BUT it is meant for downloading all your GOG games. It detects automatically if any files have changed (or are missing) regarding your GOG games, and downloads them. It also has an option to move obsole and old files away from your collection, in order to keep it tidy.

https://www.gog.com/forum/general/gogrepopy_python_script_for_regularly_backing_up_your_purchased_gog_collection_for_full_offline_e/page1

I just run gogrepo maybe twice a month or so, and I know I always have the very latest installers and files at that point. Also when you run gogrepo update, it clears those update flags that may be visible on your GOG account tab.

On the other hand, if your meaning is to just download some of your GOG games, and keep them up to date, then gogrepo isn't probably the solution.

Yes, I'd like to be told what every update is for regardless of what the reason might be, regardless whether it is critical or absolutely trivial. Even if it is "Corrected misspelling of the word "the" as "teh" in the game manual on page 27." and that's the only change. I hate it when things change and there is no known reason why and you have to play guessing games to figure it out yourself.

There are changelogs for many but not all games, and even with those changelogs, sometimes a game is updated with no changelog provided, such as the most recent update to The Witcher 3 which changed the files themselves, did not change the version number of the game, broke the game (for some people reporting it so far) and it has neither been fixed yet, nor has GOG communicated anything whatsoever about the change publicly, nor in any changelog, and they don't respond to inquiries about it either.

What's worse on a change like that, is when someone communicates about the version of the game they have they're going to say "I am using version 1.31 of the game", but then it is a whole new game to play of "Which version 1.31 of the game do you have? The original 1.31, or the silently updated changed version of 1.31 that is the same but different and broken?"

In this case solution would probably be meaningful and easy to access global update message queues for the game library, possible with filtering by game, OS, language, severity (minor, major, critical), ...

This is not really impossible, if only GOG would invest the effort to provide the infrastructure. It's 2016 already. Those things were already possible like at least 10 years ago.

And it's also something a script like gogrepo.py cannot provide since it relies on information from GOG. So if GOG does not deliver that information, no other solution possible.

Do any other digital game stores/services offer that? Can I somehow e.g. check in one swoop by filtering which of my Humble Bundle Windows/Android installers have changed, and what has changed?

gogrepo doesn't necessarily have to rely on changelogs or update notifications from GOG. It detects if any files have changed, compared to what is in your current local collection. Then it downloads the changed/new files, and new changelogs for those games that have one.

Changelogs of course must come from GOG, so if there isn't one, then you can't really tell why has there been a change. You just know it has changed.