kroetenschemel: Hmm... I'm not a doomsayer in terms people who don't understand the optional aspect, but I see another problem comming and it would be cool, if GOG has an answer to that:
Is Galaxy going to support actual older games. The old games are often using a 32bit network protocol, which you can emulate with for example hamachi. Are you making sure that each game in your catalogue is actually playable in multiplayer on Galaxy?
If *yes* how much human ressources will you have to spend on that? Is a price increase comming?
If "no", what's the point of the cross-multiplayer anyway when there's almost no games to use it with?
We'll do what we can for the older games that had/have multiplayer but this will take time and it all depends on the games themselves. Some might work, some might not, best thing to do is wait and see at this point :)