Something I'm hearing from that Comcast meeting: the materials specifically say the new park will be one of the largest they've ever built, but will still have a large amount of room for future expansion, "allowing for the 'World' of any movie, television show, video game, or more, to be featured in our brand new theme park in the future."
This goes along with other rumors that the park may not open with as many worlds as one would assume, but also means any concepts we've drawn up for how to split the land may need to leave larger holes than we thought. Sounds like they may want to avoid the problems of prior parks, and leave clear expansion plots big enough for entire worlds in place, not just for new attractions.