Released on April 2nd, 2015.
This is an alpha version. This means it is meant mainly for evaluation and testing.
The main thing to know about alpha versions is that anything might change from one release to the next and we do not guarantee a clean upgrade path from one alpha to the next.
However, this version works! There are many little details that still need to be polished but this version should start to give you a good idea of what the stable b2evolution v6 will be like ;)