I think it's related to the "Next Billion Miles" nationwide tour event. If he says the X will be available for test drives at the tour cities, well, everyone will go ape**** including the media in all those cities. Heck people will be on jets within the hour, flying to Pittsburgh, first stop on the tour this weekend.
Then again..... Friday is, as any West Wing viewer knows, "Take Out The Trash Day" in terms of news. So I agree there is a possibility of bad news tomorrow. I hope not, the stock will plummet to $200 or less.
If it's software-related or autopilot update, not so interesting to me.
But given the timing of Next Billion Miles, I'm thinking that's it... autopilot for sure, and maybe X.