This development IS actually very surprising and significant, since this is the first chinese aircraft with a tailless design.
This indicates that the chinese software and flight control development significantly matured to enable them to engage in tailless flying wing designs.
All while the apparent scaled-down model for the LiJian UCAV, the small RC model, which still had tails.
This development also could mean that future J-20 variants might feature a tailless design as well, given suitable TVC-capable engines and the solution of other problems that are inherent with supersonic tailless aircrafts.
The paper that explained the basis of the J-20 design indicated that they initially tried to go tailless but decided that it needed more yaw stability. I wouldn't expect a tailless design any time soon, though they may remove the ventral fins at some point.