It looks like from the gameplay in the video that they are using the original games source, also they are presenting themselves commercially so I am going to assume they have the required licenses. However those don't guarantee that... Also we don't know the extent, did kavcom buy the rights or license them? If someone is going to sue us for taking a part of their market share, is it going to be kavcom or bitmap brothers? Bitmap Brothers would probably be more lenient towards us where kavcom might immediately or at least try to shut us down.
The thing that strikes me is they decided to do this when this open source remake was so far along. They decided to release commercially when there is a free open source version? Really I think this is bad news.
However the pros and cons pretty much amount to this... I won't be able to formally charge for a clone of a game that is still presently commercial so throw that incentive out the window. However they are going to have to advertise and stir up interest for the game again. We can take all this new interest for the game and channel it here. Also a lot of people hold out on supporting this project with the impression that it is just an old forgotten game. It's a little hard to think of it as forgotten when they are releasing it again and betting that it'll make at least a couple of hundred thousand in sales. Folks minus one donator, this project hasn't brought in more then $100 in donations so good luck to them and shame on the z community if they actually rebuy the same old original while they ignore the open source remake / advancement.