We are approaching the release of the Temple of Elemental Evil adventure pack next week on the Lamannia test server and hopefully by the end of March on the live servers. I have noticed no official promotional material on the Internet or elsewhere about this update, which is one of the most significant additions to the game since the Menace of the Underdark expansion.
I would suggest making a 30 second promotional video for TOEE that can be shared on social media and with news outlets like Massively Overpowered and Ten Ton Hammer that cover the MMO industry. A DDO TOEE video going viral would truly help promote the game as the Temple of Elemental Evil was one of the most popular D&D modules of all time and the last time TOEE was made into a video game (Troika Games' 2003 release) it was a major success.
A number of former players aren't even aware that DDO is still kicking after 9 years, so TOEE could help pull them back into the game. TOEE will also recruit quite a few new players if enough people hear about the update. Heck, even the Shadowfell Conspiracy expansion had a 1:12 minute launch trailer.
https://www.youtube.com/watch?v=kFZisG6g2q4