Interesting... about 8 or 10 years ago, our company was contacted to supply helium by a similar venture known as "http://en.wikipedia.org/wiki/Cargolifter" ". The company was based in Germany, and had even gone as far as building an enormous hanger for the new airship.
The company was looking at a niche market - to transport oversized equipment that wouldn't otherwise be possible to move over the road, or on rail, similar to the SkyCat. At the time, it seemed like the market they were after might potentially be economical. If the blimps could tap into transporting very large equipment economically, they might find a niche market.
I guess they had many issues around this system and perhaps they eventually found it just wouldn't be economical. I suspect that's all it was. I know one of the issues was around the helium. Over a fairly short period of time, helium would diffuse out of the blimp and air would diffuse in, contaminating the helium. So every few months, the helium in the blimp would need to be 'cleaned' of air. Doing this was no small feat. They considered how to store that much gas, and came up with an idea of storing it inside an underground, concrete tube at about 1000 psig. But the size of this cavern was enormous and compressing and cleaning this very expensive gas was a serious concern. Helium today runs about $15 per 100 SCF. That’s about $500,000 for the helium alone, so you can’t just toss the gas out and put fresh in.
Perhaps the SkyCat has learned from the Cargolifter. I have to believe there are people in the SkyCat organization that came from Cargolifter. That’s typical of industry. Knowing that, there may be some hope for SkyCat, but it really depends on the ability of the company to find this niche market where they can maintain an economic advantage.