There was a post on LaughingPlace recently that indirectly spoke about this topic, with the info coming straight from Marty Sklar. The short answer is that there isn't much currently planned for WDW, and specifically the Magic Kingdom Park, after Everest opens.
The transcript of the LaughingPlace post is as follows;
"So I had to fly to Portland early Friday morning, so my Thursday night was packed... thus the reason I didn't post this until now.
I had a meeting Thursday afternoon at WDI, and chatted with Marty Sklar - my first time having a real conversation with the guy, and I wasn't actually expecting to meet him that day. But he's genuine and sweet, albeit a tad world-weary. Still very optimistic...
We talked a bit about DCA, and he said this issue is front and center and that they are working hard on plans to really breathe new life into the place.
Aside from that, not a whole lot to tell, except for the sad news that Magic Kingdom in WDW probably shouldn't expect any e-tickets for quite a long time. And design work has begun for Shanghai, but everyone here knew that already. I don't know how far along the are.
There is now a beautiful tribute to John Hench in one of the hallways at WDI, not too far from their little commissary... it's a fitting collection of tributes written and painted by a number of people who knew and were influenced by him... taking various forms. I haven't been to the Glendale campus in about three years, and so this was pretty new.
Anyway, it was nice to hear from the horse's mouth that his attention is focused on "fixing" (yes, that was a term used) DCA."
I wouldn't count on much coming to WDW before the end of the decade, aside from Everest and smaller attraction nips and tucks.
I do think it's good they are focusing on DCA as the Priority One for American parks; I was at Disneyland today and it was it's usual packed and busy Saturday self; with busy queues for all the rides and parades and Fantasmic! and fireworks and both dancefloors full of local kids twisting the night away at another Date Nite at Disneyland. But 100 yards to the south of Disneyland, DCA was very quiet and had very few people wandering around without much going on. A gorgeously cool and crisp late summer evening in SoCal, and everyone seemed to want to be at Disneyland instead of DCA.
DCA is obviously in need of more attention that the WDW parks at this time.