As a fan of Dark Souls, and as Someone who's watched this thread unfold, I'm going to make myself very clear here; in the grand scheme of things, this is a complete non-issue. Now, I perfectly understand that people are on a complete blackout and who haven't bitten the bullet and got the game early via import or the Xbox exploit for when the game comes out next Tuesday. That's fine, I get that. But we're talking about a weapon that has shown up in two games already, regardless of its name or graphical look and design, and was explicitly made for the release of Dark Souls 3 as advertising for the game. It stands to reason that, potentially, this weapon could show up again amongst the likes of other weapons, such as the Moonlight Greatsword, or even items such as rings that've shown up the other two games, such the life ring or the covetous serpent rings. Furthermore, it does not explicitly state within the video that the sword shows up in Dark Souls, or even it goes by that name any more were it to show in Dark Souls 3.
Ultimately, as much as Artorias is beloved by much of the fanbase, and as much as his greatsword is iconic to most of us, it's just a sword. That's all it is. A unique sword, and one that I'm sure a lot of people would love to see in Dark Souls 3, but it's a virtual sword from a well-known, but ultimately a video game series that in a year from now, isn't going to help myself or anyone else here with our day to day jobs or lives, and isn't any real revelation with what goes on in the real world. Once again, I get why people feel aggrieved about potential spoilers for Dark Souls 3, but take it from me as someone who's had a rough patch in real life, when compared to virtually unlimited amounts of things that could happen to anyone at anytime in life, this isn't something that people should be massively hung up about.
Anyway, that's my two cents and on topic of the video, it's a lovely weapon, but I imagine it must be heavy as fuck to hold up. No bloody wonder they just let it drop onto things in the demos, rather than attempting to swing the damn thing.