The latest version of Amiga Forever is Amiga Forever 2016. If you purchased Amiga Forever 2014 after September 1st, 2015, then the 2016 version is a free update for you (you will be contacted by email shortly after the release).
If you purchased any previous version (1.0 to 2014), you may purchase Amiga Forever 2016 Plus Edition or Premium Edition at upgrade conditions.
Minor software updates between different revisions (e.g. 2014.0.0.0 to 2014.2.0.0) are free. Please use the built-in Check for Updates functionality (Help menu) to install these.
The video content of the two DVDs has not changed between the 2005-2011 versions, however a new video (included both as DVD and WMV HD file) was added to the 2012-2016 versions.
Upgrades to Amiga Explorer are always free (just re-download).