When I read this, I immediately thought of Kojima's remarks from December of last year.
"Development on Death Stranding is going well enough that SIE told us, 'We have never before seen a game being created at such a fast pace.' We are planning an announcement that will further surprise everyone in 2018."
In all honesty, for me, expectations, in regard to this comment, have been tempered. The Death Stranding subreddit mentions it every other day, as do other subsects of the community. I just wrote it off, like, it's just Kojima being Kojima. "It's probably the Lindsay Wagner reveal." After allowing the MGS community to brainwash me into thinking the Christmas day presentation of 2014 was going to be more than a Chicken Hat reveal, I prefer to keep things in perspective. That, and the "Players will be able to revisit Camp Omega" bit. But with Geoff's tweet, mentioning things he's held onto for about a year now - it makes me wonder if the surprise announcement is, in fact, something substantial, and if it will be present during TGA 2018.
We're just over a week away. Looking forward to learning more soon.