Here's my thoughts so far:
+ I'm disappointed this is just more of Night City. I was one of the people who was really hoping to get to do some stuff in space.
+ It absolutely is during the main story since we have Johnny, so no new endings or ending material.
+ I'm glad we're getting some more Presidential stuff.
+ I hope Morgan Blackhand is going to be in this section but I doubt it.
+ I don't think this will be a particularly large expansion and I expect something more Heart of Stone than Blood and Wine, which was really The Witcher 3.5.
+ Saving the President is a nice homage to ESCAPE FROM NEW YORK.
+ Johnny actually may get some decent character development due to being an ex-Marine. V's thoughts on whether Night City is better under the control of Arasaka or America (Militech?) is an interesting question. It may be a "lesser of two evils" situation.
+ I am curious at the release time but I'm okay with upgrading by 2023.
+ I do hope we'll get a lot of Militech expansionism.
+ Sadly, I feel like the lack of any expansion on V means that the inevitable Cyberpunk 2080 game will not have them as the protagonist. Which is all I want.