If it's like last year Friday will be the big animation presentation, Saturday live action and parks, and Sunday gaming.
Animation- They showed clips from Good Dinosaur (scene with the sticks), Zootopia (ice cream shop and DMV) Dory (scene where she arrives at the aquarium), and Moana (baby Moana). They also performed a song from Moana. So I'd assume there'd be some Wreck it Ralph and Coco (they showed some concept last year) clips. They'll probably have more on Gigantic- they played a song (terrible, terrible song) and showed some storyboard work last year.
Live Action- they started with Marvel. Concept art of Dr. Strange, CA:CW trailer. There will probably be some Thor and Black Panther footage, maybe concept art from Infinity War and Ant-man and Wasp? After that was WDS. Clip from Finest Hours (scene where Miriam talks about marrying Bernie), trailers for Pete's Dragons, Alice, Jungle Book. Johnny Depp showed up as Jack Sparrow and they announced more cast, and talked about Queen of Katwe. This is probably the most unknown, as a lot of movies haven't been officially announced for 2018 yet. There's a lot of "Untitled Live Action" listed. But there will maybe be something Mary Poppins? Then Star Wars. They announced Star Wars land at the film panel and had the cast there and that was pretty much it. Soooo I dunno. Star Wars VIII comes out that winter and Han Solo the following year, so there might be more? If you want to attend this panel I'd overnight it. I didn't and I was one of the last people in last year and I only expect it to get more popular/crowded.
Parks- Not particularly full panel last year. They talked about Shanghai and the new HK Iron Man ride. Then Toy Story and Star Wars and new Soarin. Oh, and night time AK. I'd expect maybe more concrete details on Star Wars, Toy Story, and maybe Avatar (when is that supposed to open?). Probably talk about the retheming of ToT at DL. Probably confirm more rumors (Marvel land at DL? GotG at Epcot?) Not sure about international parks, but they'll talk about them, too.
Outside those panels, there will probably be some stuff on Star Wars (there were costumes last year) and Wreck It Ralph might have a section dedicated to it (Zootopia had a bit). I'm hoping there will be some more TV stuff- that's what my BIL works on. I'd expect the Pizza Planet truck to be there again. And that's all I can really guess now.