Sounds like some interesting ideas.
I think it may well come back in some form (network, cable, DVD premiere, movies, even paid downloads). BUT a few words of warning:
* That link is NOT an official site in any way. Just something created for (and probably by) fans like us.
* No word should be expected any time soon. Joss Whedon has repeatedly said that any return of these characters is something he'll be keeping in mind long-term, not something that's likely any time soon. (He's got other projects going too, of course.)
* Whedonesque.org has warned several times against taking these EXTERNAL projects too seriously. In fact, some (I'm NOT pointing fingers at that link in particular) may simply be playing off of a fan market for profit (be it click-throughs or actually collecting donations).
I'm not saying these project(s) aren't worth supporting--but I'm saying it's likely to be so unofficial and remote from any actual control over what happens that we should take it for what it is... but not taken TOO seriously.
Now, that said... cool site, and thanks for the link!

I went ahead and answered their survey (anonymously and safe from any spam fear). Keeping up Firefly activity of different kinds is good--especially if it leads to more people discovering and enjoying (and renting and buying) Serenity and Firefly.
(And don't forget to keep tuning in to the various FF/Serenity podcasts on iTunes, like The Signal and Firefly Talk. I've only caught a few, but they were fun.)
PS, Supposedly the movie has already become profitable from DVD sales/rentals. If so, that seems to be well ahead of other movies that have gotten sequels. And the DVD reviews are rolling out, just as glowing across the board as the movie reviews were.