Computers games have done everything that ebooks are doing now. The ereader is just a much more portable computer and the ebook is still just a story whether it's mostly words, or not.
- What if your book had moving or scrolling text? Computer games already did it.
- What if your book played music composed specifically for the current chapter of the story? Computer games already did it.
- What if your book included moving images, videos, changing backgrounds, mood lighting? Computer games already did it.
- What if there were no words at all, but sweeping musical scores, scenes performed by actors and explosions? Jerry Bruckheimer already did it..
And one day your book will just be a movie, but you'll still tell everyone you're reading.