The single player is available now, and you can do co-op through LAN. Still pretty lame they weren't able to get Galaxy up and running in time. There was a serious lack of communication from both GoG and Larian. Even the official statement on GoG made it sound like the game wouldn't be available till August. There was also an issue in the Larian vault page regarding the selection of platform. Fortunately, everything seems sorted out now. I was able to redeem my code and the game is now in my library.
...nevermind. When I try to DL I get an error page. Apparently the game isn't available yet. WTF GoG??