A few days ago, Microsoft stated that it "continues to support the Games for Windows Live platform," however it seems like "continue to support" wasn't exactly what we thought it would be. According to a deleted update on the Age of Empires Online's support page, the PC games service will come to an end next July, with Age of Empire's Online closing its servers at the same time.
Microsoft posted the following update on the Age of Empires Online support page on Xbox.com earlier today, but later removed it. "Games for Windows Live will be discontinued on July 1, 2014. Although it is available through Steam, Age of Empires Online requires features of the Games for Windows Live service. You can continue to enjoy all the features of Age of Empires Online as the service will remain 100% operational until July 1, 2014 when the server will shut down."
At the moment, we are not sure how will this affect players that purchased games on the service such as Dark Souls, Fable 3, among others.