The Catholic church has only been around for about 2,000 years. For comparison on these time scales, note that none of what we now view as "primitive" religions from the ancient world persist today. On top of that, I believe that even though the world is highly religious today, it is one movement I'd imagine to be in significant danger going into the far future.
The Catholic church is one of the, if not the oldest institution. Also, the world has always been religious, and it's not significantly becoming less so just yet. So there's no indication of that going away.
There's no mention of a DVD release date on any of the pages I can find, anyone know if it's in the works? Having to fly to the UK to watch it is a bit of a non-starter.