My dearest Sue, I wish I had an accurate copy of an agenda for D23, but Zenia's crew has apparently left me off the email list (yeah, convenient, I know).
Disney knows it HAS to make a splash in its P&R presentation if it has any hopes of the Expo continuing.They set a high bar (relatively speaking) in 2009 and then completely ignored it in 2011. Between that and the complaints of people who paid and waited in endless lines (for the good stuff) only to not get in, they can't have a repeat.
Now, the question is what is a big splash? Is it announcing one of the new projects for DLR (with a largely SoCal crowd)? Is it showing off more of Shanghai now that construction has actually started? Is it wowing the fanbois with something that they worked on with Cameron's folks to FINALLY tell us what we'll get in Pandora after waiting six years for it to open? Is it showing off the Ratatouille ride that will open in DSP next summer? Is it announcing what will be in the new Marvel land at HKDL? OR ... is it going big and announcing a DCA-style makeover for TPFKaTD-MGMS? Or announcing they aren't going big, but still putting some money and effort into the park?
Now, if it were me, I'd do ALL of the above. I'd blow people's socks off and get them excited about what Disney is doing around the world in the rest of the decade.
But this is Disney, they may show a mockup of one of the MK's new floats and do a presentation on the kiddie coaster coming and the recently opened Fantasy Faire at DL and call it a day.