If you read interviews with basically anyone in Behemoth, you get the same answer about a new album – it'll happen when it happens, if it's going to happen at all. We know that the band had shown it was definitively working on some new material in March, but now we've got some actual, full-band music to check out.
The song, or what may become a song or a portion of a song, is surprisingly punky and has a killer d-beat sort of feel to it. I guess that really isn't too surprising, considering the group had previously stated that the new stuff would likely be influenced by post-punk!
Either way, I think it's safe to assume this is not Nergal's folk project.