[Katsunami]

Good point... Maybe the fact that epub is so easily created, or dissected and converted back to flat text, may cause it to be passed up by the big companies in the long run. Wouldn't be the first time that the common sense of portability, convenience and being future proof lost to the raw power of money.

(And yes, being able to create or dissect an ebook using a notepad and a zip utility only is what I call portable, convenient, and future proof. Also, you're not tied to any operating system to do it. Sigil just makes everything easier, but is not actually required.)