Disruptive Innovations, developer of the BlueGriffon website editor, posted a teaser on its blog yesterday.
It plans to release a new stand-alone version of BlueGriffon in the near future which will support creating new Epub as well as editing Epub made elsewhere. Unlike the Sigil Epub editor, this will be a commercial app. The new app is going to be able to edit all parts of an Epub, both the metadata or the contents. It will be simple, powerful, and according to DI it will also strictly conform to W3C and IDPF standards.
There’s no word on the release date or the price. There’s also no mention yet of whether this app will support Epub 3, and that’s an important question. The app might be released before the standard is finalized, which means there’s a chance that the standard might invalidate Epubs made by the app.