I wouldn't give up hope. Back in the 60s, fan support kept Star Trek from being cancelled sooner than it was. And this was way before the internet and all the cable outlets available these days.
It wouldn't surprise me if the producers are looking at alternatives to make and broadcast the remainder of the season somewhere. It may be on UPN, FX, USA, or another cable network, and may not happen immediately if it does, but I'm sure they're going to try.
I'm just not sure if they'll make the remaining 8 episodes and release the whole series on DVD. I'm sure there were plans for a DVD release at one point. Has a series ever produced any new unaired episodes specifically for the DVD release? The Firefly DVD included three unaired episodes but those were already made.