According to the changelog, the update makes a couple changes to the interface, fixes a bug with deauthorized computers, and adds support for a few additional features from the Epub3 spec.
Adobe DE 4 now supports new ways to navigate ebooks, and it can also finally display equations in MathML. There's also mention that video and audio content can be progressively downloaded, freeing up a reader to start watching immediately.
- Support is now available for navigational items like Landmarks, Pages list, Images list and Tables list.
- MathML support is now available for ADE on Windows.
- Audio and video content in the eBooks can be progressively downloaded on all platforms.
- Erasing the authorization of this computer adds one more to your number of allowed authorizations.
- An intuitive popup box for controlling media overlays.
- The Scrubber bar can be used to navigate to pages across eBooks.
- Full support for EPUB’s Fragment Identifier.
- Full support for all input types in eBooks.