Quoth Nathan Fillion in the interview: "Yes. Yes. I would examine very closely Fox’s reasoning — I’m a little gun-shy. If I got $300 million from the California Lottery, the first thing I would do is buy the rights to Firefly, make it on my own, and distribute it on the Internet."
Note that he's still committed to doing Castle, and the only definite thing giving Fillion the rights would get is free Firely for all. That's a good thing, but it's not new Firefly. What Fillion did not say is "I wish I had $300 million so I could make new Firefly episodes." Of course, Firefly isn't Firefly without Joss Whedon, and he has said nothing.
Regardless of his intentions however, the point of this website and the project behind it is to convince them both to do new episodes. It's a long shot, sure, but that is precisely what they intend. See the FAQ.
