Age of Empires Online has ceased active development and is now shifting into a "support" phase. That means no new content or features are coming, other than a few remaining minor updates that will be released over the next few weeks. Gas Powered Games says it still plans to support the game with Community Challenges, streams, contests, and PvP tournaments.
Devoted AOE Online players can still play the game, though, and GPG stresses in a FAQ that the game is not "dying." It does note that bug fixes will be slower, and some might be "unfixable," but it will be watching out for critical bugs.
The blog notes that making new content is "too expensive to maintain for long, as it turns out. We can no longer afford to keep creating it. AOEO already has a very large amount of high-quality, hand-crafted entertainment, and adding more is no longer cost-effective."
Meanwhile, Gas Powered has already started teasing its next project, so the end of development and slower bug support could signal moving staff to the new title.