So what kind of hints do we have:
- The blattant statement that it is not Victoria 3 by Henrik
- The con is held in Berlin (could be indicating cold war, Bismarck, or WW1)
- Chris King didn't show up in the video (could be a hint that it's his game, or the opposite)
- Martin Anward stated that they would announce something new (could be a hint that it is his game)
Based on this my guess would be that it's Martin Anwards game, an anouncement IMO is a directors moment to shine, IMO it wouldn't make much sense to not include that guy as some hint or something like that. I feel that Berlin is not a hint but Germany is just a logical place for a Con outside of Sweden. I also tend to believe them with denying Victoria 3, they've seen how annoying it is to have people believe their golden boy is going to be announced and be disapointed. I feel considering the rabid Vicky fanboys it's the smart choice to play it down early and hard and not mess around it anymore.
My guess would be Martin Anwards new fantasy GSG with random world map. My own ideas which probably are in no way in line with the reality would be that there shoul be added a great, random gameplay variety based on some options before a new game. Will you play a magic oriented race, or a steampunkt technology focussed race, or religious nutcases, or demonsummoning, or nature lovers, or necromancers, etc., do you play the last remnants of a fallen empire, a horde tribe just arriving on your start position or and up and coming kingdom or republic, etc.