Older games don't really get many updates at all very often so it isn't a huge problem with them. The problem is more with regards to much newer games that might get frequent updates. GOG's current update mechanism does not work too well with this and it will vary from game to game what works best. The approach taken by more modern update mechanisms is superior technically, and in the case of GOG just need to be implemented in a way that allows people to have their desired functionality without any big tradeoffs. I believe that it's not only doable, but that GOG has the engineering talent to give everyone their cake and let them eat it too. I've personally had to implement a modern updater that handled binary deltas between arbitrary versions of software while doing caching and allowing the local files to be reused without Internet connectivity and it's really not that difficult. Most of the functionality exists in off the shelf tools that just need to be glued together. I use libcurl for that sort of thing myself and the rest of it is child's play. From a technical perspective,

Personally, I could easily write a downloader client in C which would both have the ability to duplicate the functionality of the existing GOG downloader exactly while at the same time keeping network traffic as low as possible whenever possible for backward compatibility with what people seem to want to stay the same, while also having a more modern method which sounds like what the Galaxy client will provide that will work better for cases the current downloader doesn't. I have faith that if I can think of how to go about doing that, GOG totally can do something like that too. ;)

In my observation of the GOG community threads it seems to be broken into two camps for the most part. One is people who dislike or fear Steam/Origin/Uplay and similar clients/services for whatever their own reasons are and just fear GOG is going to do the same thing and they'll be forced to swallow it up and they don't want to see that happen so they need to make their voices heard loudly so that GOG knows they're here and they wont stand for that. That's ok too because it is important for everyone to express what they want and don't want so that it is documented and known. The other group seems to mainly be concerned with worrying about losing features/functionality either from the existing GOG Downloader and/or the GOG website and/or otherwise losing control over their experience as a GOG customer somehow, and they want strong assurances that they will be able to have their individual needs and expectations met in the future when Galaxy arrives, but since the information on Galaxy is a bit scarce and not too detailed yet people fear that it may not meet their expectations, some making assumptions that they will be disenfranchised and feel there is nothing that will prevent them from being dissatisfied in the end.

With the lack of information details we have there's no way to get the answers everyone seeks just yet other than to wait for more information to come along. People certainly have a right to feel however they might feel and to have their personal concerns. I'd like to see everyone end up having any important concerns met in the end and I think GOG can do this, but at the same time you can't make an omelette without breaking a few eggs too. :)

GOG has stated that they are indeed watching the forums closely and discussing people's concerns in their meetings and trying to ensure that what they are doing will be able to meet the needs of the community without leaving people behind (my own paraphrasing). No matter what they do there WILL be some people angry about it however, even if they gave every customer $10,000 each, there will be people pissed off about it, that's human nature. :) They shouldn't try to please everyone though (when you try to please everyone you usually end up pleasing no one), but rather they should do the best job they can, and then make improvements based on feedback of what can be improved until hopefully the majority of people think they hit the nail on the head.

I have faith they have all of our interests at heart and will try to provide all of us with a better experience in the end though even if there are any bumps along the way, and they will definitely have my patience and understanding even if I end up being negatively affected in any way. I trust them to fix anything that they might break or mess up, and if I don't like something I'll try to tell them about it professionally and hope to see them address it. ;)

The wiki states that the official downloader is a mix of C# and .NET. Yeah. I'm familiar with C++. The amount of control you get over memory and object usage is quite nice.

I was of the opinion that memory usage tends to scale with the amount of available memory, my system uses 144mb on steam front page while GoG is sitting at 42mb.

I wonder if they have any statistics on their userbase, I'd be interested to know what the oldest machine running GoG games is...

They probably don't have any real hard numbers on that since people never need to tell them via the web interface (nor is there a way to do it), and people can freely download their game library solely through the web browser if they wish and then install the game(s) offline without ever connecting to the Internet, plus the games installers never phone home or anything like that. If they were going to submit any details about people's systems they would have to inform the consumer first and ask for approval or they'd certainly violate the privacy laws of some countries.

Steam has opt-in surveys for doing this that you have to choose to do, and then it gathers all the info Valve wants, lets you see all of it so you know what it is about to submit and then you get to choose whether to send it to Valve. I went through that process once just to see what all Valve was collecting. I was ok with 99% of what Valve collected until I got to the part where they scan and create a list of all of the software applications you have installed on your system (not just games), at which point I felt that information was none of Valve's business and cancelled myself out of their survey because there was no way to selectively exclude anything from their harvester, but I didn't feel that Valve was trying to pull one over on me either as they very clearly showed what data they wanted to collect and gave the opportunity to opt out.

I've never seen GOG do a survey before so I'm not sure how they would be able to obtain this information from their customer base in any manner, so they probably don't have such info. Mind you, Valve makes the results of their surveys publicly available through Steam and that information is very useful to game developers, gamers, and even Valve's own competition as far as knowing what types of computer systems people are using at large and how the breakdown of parts is. A lot of the statistics are quite surprising too and not what one might expect at all. :) Here is a link to Valve's statistics that you might find interesting, I know I did:

http://store.steampowered.com/hwsurvey

If we use that as a guide, GOG's userbase probably statistically is similar to the data gathered by Steam in which case the oldest computer systems show up in the stats as: "Below 1.4 Ghz - 0.42%" The details don't appear to go more finer grained than that though, but a lot of very fascinating data to peruse there. :)

Wow. That's pretty neat. Thanks for sharing!

Indeed, the existing system at GOG is sufficient for many people and will likely be kept but insufficient for everyone out there and especially poor for new games that get frequent updates. Galaxy is allegedly being designed to address that in a way that is most likely similar to what you're describing I imagine or we can hope at least. Delta updates have been around for eons as a concept but just underused.

You can disable auto-updates on Steam on a game by game basis by the way and then manage them yourself manually. It will still tell you an update is available and some games may require you to install the update before playing but it is still quite useful to prevent games from updating every 5 minutes over and over when you're not actually playing them and they get lots of updates (TF2, DOTA2, PoE, etc.) I usually disable updates on every game and then do them manually to avoid surprises. I believe GOG said functionality like that would be in Galaxy client also.

You do make a good point also that delta updates produced for Galaxy back end infrastructure could also be made available for direct download and that would be a good benefit to standalone downloaders too IMHO. Furthermore the installer could be updated to look for patches named a certain way and install them by default also with option to back off to any particular user selected version. That would be great and more flexible for everyone pretty much (Galaxy users or not).

Now we just have to chew our nails, watch paint dry and wait... :)