Other than the announcement, there is a summary in a D:OS 2 Kickstarter update, and there was a Twitch stream about the EE (specifically the harder difficulty mode) were some differences and features were discussed. The stream cut out a few times near the start, so it is in multiple pieces:

http://www.twitch.tv/larianstudios/v/18449870

http://www.twitch.tv/larianstudios/v/18450055

http://www.twitch.tv/larianstudios/v/18450304

http://www.twitch.tv/larianstudios/v/18450441

http://www.twitch.tv/larianstudios/v/18451386