Some information about the Pokemon X and Pokemon Y strategy guides for Japan have come out during The Pokemon Game Show. The regular guide will be 262 pages long, six pages longer than the english hardcover guidebook is expected to be. A “Story Guide” is coming out in November and will be a massive 600 pages long. The Kalos Pokedex guide will be 800 pages long and will be released in December in Japan.
There isn’t much details so far about what this story guide may be, but it’s quite possible it will be more of a collectors item similar to The Legend of Zelda’s Hyrule Historia and less of a functional guide. If that’s the case and it ends up not just being an extended guide, hopefully we will get an announcement of an overseas release soon as well.