The bid books have been released by FIFA and can be read here: http://www.fifa.com/about-fifa/news/y=2018/m=3/news=2026-fifa-world-cup-bid-books-now-available.html
It's long as hell so I'm not planning on reading it, but the two big things to glean from it according to a writer from the Sports Business Journal are that it would have three concurrent kickoff matches to start the tournament with the main match in Los Angeles or Mexico City and the proposed sites are Arlington and Atlanta for the Semifinals and New York/New Jersey for the Final.