Well, this is all news to me and I find this thread fascinating. I believe I have some insight into the situation because I actually lived in Las Vegas for 4 months, from New Years through April 1997. (It was very much against my better judgment, but my wife at the time wanted more excitement than Tucson had to offer and took a job there and said she was going and if I wanted to stay with her that was it, and then after less than four months there she divorced me anyway).
1) Las Vegas desperately needs a zoo. Maybe not so much for the tourists (who do go solely to gamble and party and see the shows), but for the locals. I think about a million people live there now and there is NOTHING to do in that city aside from the casinos. No major museums, no theme parks or zoos, not even a major city park like every other American city has. It is just an awful place to live IMO.
2) Desert/water conservation MUST be a central message of the zoo (whoever builds it). Tucson has a very strong conservation ethic and the per capita water use is well below all other major desert cities - about half that of Las Vegas residents. I am sure this is largely due to the longstanding efforts of the Arizona Sonora Desert Museum.
3) Apparently headline writers in Australia are not required to know geography, because they think Las Vegas, Nevada is a suburb of Los Angeles, California.
4) If I were Australian, I would be upset about my local zoo spending 300 million on an overseas zoo and neglecting projects at home.
5) In conclusion: I am 100% in favor of SOMEONE building a zoo in Las Vegas, but I am not sure these are the people to do it. I know of at least two other previous efforts that have come to nothing. The first was by the disgusting small roadside zoo that already exists there (Southern Nevada Zoo). When I was living there they had bought land outside the city for a major wildlife park that never happened (yet, anyway). The second was a local couple I read about recently that were trying to line up investors. That one still may be an option. If a real zoo does ever get built, it might even give me a reason to return to that depressing city that I would otherwise never step foot in again (except perhaps to change planes in the airport).