Good news for AoE fans. Forgotten Empires has received the official expansion status for Age of Empires 2 HD, and we have some details on that. This was originally a fan made expansion pack and the hard work put behind it has finally paid off.

It will be released in fall 2013 on Steam. Here are some details on it:

Proper spectator features

Twitch.tv integration (including chat ingame)

Forgotten Empires civs, units, tech tree and balance changes (can be toggled on and off at will in settings)

New game modes: Treaty (no rush mode), Capture the Relic (akin to neutral flag CTF)

New campaigns: Four new campaigns, all set in the Italian peninsula over its long and messy history (Fall of Rome, Mercenary fighters, the Byzantine campaigns to reconquer Italy, etc).

New map size: Ludicrous (4x the area of the previous largest)

New map scripts: Acropolis, Golden Pit, new Megarandom, etc.

New AI: Uses competitive builds and does not cheat.

ETA: Fall 2013, Steam only

The announcement happened at a TwitchTV stream which can be viewed here.

Forgotten Empires features 5 new civilizations, 30 new technologies, 9 new units, and the population limit has been increased to 1000. There are also 11 new maps and it supports unlimited resolutions. Their official website offers more details.