I thought that this was very interesting. The first video made some big claims and became very controversial even attracting the attention of Notch. Correct me if I'm wrong but I believe that Notch called them out because they claimed that their engine was not a voxel engine but Notch believed that it fundamentally was in fact one. It all seems very shady, I wish that they would release some more videos or a demo to prove their legitimacy.
I also found this engine called Atamontage
that is like Euclideon's except Atamontage uses voxels in order to obtain detail. But this project also hasn't been updated in a while.