Although it doesn’t seem that interesting, the side plot involving Ender’s siblings, Valentine and Peter, taking over the world’s politics one internet forum at a time is one of the more important events to the series as a whole. In fact, almost everything after the Third Invasion hinges on the political prowess of Peter.
With that being said, there wouldn’t be much material to translate to film, as Card himself pointed out, “that’s just watching people type things into the computer.” Although it’s definitely not as interesting as Battle School, movies like Phone Booth and Buried have made the best of a bare situation. Maybe they can type in slow motion, or during a gunfight? Work your magic, Card!
The kids’ alter egos, Locke and Demosthenes, are used to shape the political future of Earth, and much of the series’ future depends on this development, especially when dealing with Peter. Although he serves as a foil for Ender, he becomes an extremely important character soon after the Third Invasion.
Again, this all rests on the guess that the series will be taken even further in film. Card himself said when he was initially working on the screenplay that he would take this part out completely, so whether it will remain an integral plot point or not won’t be clear until Ender’s Game hits theaters.