This looks fun, I'll play. My predictions for Parks announcements at D23 Expo:
Star Tours 2 (Disneyland and Walt Disney World. No brainer for 2011 in Disneyland, per Al Lutz)
Captain EO (Disneyland in January, per Al Lutz; maybe Epcot too, but not a peep about that from anyone yet)
Cars Land model/exhibit (Only for Anaheim, obviously)
New Mr. Lincoln animatronic (For Disneyland only)
Little Mermaid (For Anaheim in 2011, with possible New Fantasyland for WDW announcement)
And I think that's about it for big Parks announcements at D23 Expo. But...
They haven't said a word about displaying anything related to Little Mermaid that opens in 2011 in Anaheim, yet they've made a huge deal about the big Cars Land exhibit they are going to have and that doesn't open until 2012. So maybe that's the big secret element? They want to reveal that Little Mermaid opens in both Anaheim and Orlando in 2011, with an attached makeover for WDW's Fantasyland in the process?
Maybe a few minor items like the Hat Box Ghost coming back to Disneyland's Haunted Mansion in January, or a sneak peek at Space Mountain Ghost Galaxy opening at Disneyland September 25th. But we already knew about Ghost Galaxy, so that would just be PR fluff over any concrete news. Hat Box Ghost is just playing to the rabid fanboi community, and they know it.
Unless they go really big on the WDW Fantasyland makeover news, most of the Parks stuff at 23 Expo appears to be about Anaheim instead of Orlando.