Wishbone: Well, that
is good news! Looking forward to it :-)
On the topic of Galaxy multiplayer, I'm actually not sure I like the idea at all. At any rate, it depends on how it is implemented. If, at any step in the process, the multiplayer functionality relies on infrastructure from GOG or CDPR, then it's really just as bad as any other proprietary multiplayer system. We've all seen what happened to GameSpy. If the system means that games will stop working (at least for multiplayer) if GOG should ever go out of business, then it's a bad system.
You can't really have a multiplayer matchmaking service that doesn't connect to a centralized server due to the very nature of it from a technical standpoint. The purpose is so that people who want to play a game can auto-locate other people who want to play a game. Now on a LAN that is simply done via UDP broadcast to probe the local network segment to either find a game server that is running, or for the game server to announce itself to any clients to display in a chooser window. It's easy, automatic and works on a LAN segment, but UDP broadcasts do not travel beyond the LAN. The only way for a game to discover other players outside of a LAN is via connecting to a known server at a known domain/address to basically either say "Give me the list of games that are up and running." or to say "Hey, I have a game up and running, let everyone else know about it." That can only happen if the game knows the hostname to connect to, and it can only do that if the game came with the host preconfigured or using some other method of obtaining the information which itself relies on centralized infrastructure (such as TXT records in DNS for example). Without a centralized server you basically do not have any way to have multiplayer matchmaking at all and that is a rather important service that is greatly desired for multiplayer games. I'd go as far as saying more people who play multiplayer demand that feature than do not.
So it really boils down to:
1) Does the audience for the game in question have a high enough interest in multiplayer matchmaking being available?
Answer: This is going to be true in 2014 for just about every game that is made. While some people don't care about multiplayer at all whatsoever, and others only are interested in LAN and/or Direct-IP, there are boatloads of people who want to connect somewhere and find players to play with whom they don't know about at all. This pretty much makes this feature a must-have for any serious game.
2) Does the game publisher want to offer their gamers multiplayer matchmaking?
Answer: Why wouldn't they? It is probably the most common way that people connect together in 2014 and play multiplayer games realistically, again whether some people care about multiplayer or not, and whether or not some people only want or care about LAN or Direct-IP. A publisher would be foolish to not include such features in any games they're developing because there are people who want it and would find it odd for a new game to not have it nowadays. It's a feature that's been around for 15 years or so that gamers are used to and expect. Since it makes it easy for people to play multiplayer and find someone to play with, this encourages people to play that game multiplayer and allows communities of gamers, clans, groups, etc. to come together and make a rich social system for playing that game. It draws more people to buy the game so that they can do this and ultimately makes the game company more money.
3) Does the existence of this feature affect someone who only wants to ever play single player games, LAN multiplayer or Direct-IP multiplayer assuming those features are present in the game by its design?
Answer: No, not at all. If someone does not want to use an optional feature of a game or other software - just don't use it, nobody is forced to use a multiplayer matchmaking service in their games if they only want to play the single player, LAN or Direct-IP mode of the game in question. Just don't use the feature and let people who want to actually use it get what they want too. Both groups of people are happy about what they get, and the game company is happy because people who can find players to play with keep their game alive for many more years than if they did not have this feature.
4) So since a central server is needed in order for the entire concept to even function one way or another no matter how you slice it, whether it is through a custom service, DNS queries or some other centralized discovery mechanism - who should run it?
Answer: There aren't a lot of viable options really. It really boils down to the game developer, the publisher, the distributor or some centralized third party service (ie: Gamespy).
5) Why don't they make it so the gamers themselves can run their own multiplayer matchmaking service instead?
Answer: They could make it so that gamers could independently run their own service that acts similarly to how a centrally controlled service mentioned above would work but the problem with that is that person 1's game that just got installed has no idea what computer on the Internet to connect to to know that person 4938 is running a multiplayer matchmaking service for the game on their computer. The only way to know that person 4938 is running the service is either for person 1's game to connect somewhere online centrally that can tell them this information or to force every gamer who wants to have this feature to have to punch in the IP address of someone else's server without having a way to know what it is, unless it is a friend of theirs or something. You essentially end up without matchmaking, but with Direct-IP, or a crossbreed between the two which is a whole different thing than any of the other options really. Having this as a feature is possible but it isn't an "instead of" feature, but it would be a possible "in addition to", meaning for example that a game that added this functionality would say have the ability to connect to the game company's dedicated servers for regular matchmaking, or another option that essentially is "Type in the hostname/IP of the matchmaking provider you prefer to use." Even with that option, there are people who want a central "official" game service to use.
I've got some other thoughts I'd like to share in another comment below which I think are important for people to think about also...