They're going to live-stream the whole floor throughout Gamescom. The original plan was no big show/event but to bring some known streamers over with them and i suspect throughout they'd have mini-announcements like at 11am, 2pm & 5pm where they'd unveil something new, and they'd have streamers filling those gaps with their usual activity and with CIG giving away ships throughout, too.
However only a couple of weeks ago they decided they had enough material to warrant having a proper broadcast event at the night, like we see with PAX, CitCon and past Gamescom events... so if the surprises are being saved for the big event, i'd imagine the daily streams will be less impressive than intended - possibly to the point of it seeming pointless flying people in to simply do what they'd do from home any other day.
The meaningful live event is set for Fri 19th at 8pm, which means i wont see this or the football that night, cos i'll have relatives round for the depressing anniversary of me getting another year older
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x3
Im pretty sure the procedural planets & landings will be one highlight, its the perfect time seeing as they're in Germany, like SQ42 showcased at CitCon last year. After that, who knows. With CitCon only 8 weeks after Gamescom they need 2 shows worth of content without having too much of it being very similar to the previous event (they both had a multi-crew demo last year which were pretty similar, but a first showing and an updated showing didnt feel repetitive), so while they could have ProcGen and SQ42 stuff, they wont want to lose stuff they'd planned for 10/10 (11th i think this year, the first time its not been held on 10/10).