I don't think you'll see this soon. Here in Washington, we did away with smoking in public places a while back. The private mini-casinos (card games only, BJ, LIR etc.) were barely surviving with competition from the full service tribal casinos. When the law took effect, it devistated these operations and even many of the bars that sold pulltabs. A nonsmoking casino in Vegas would be an experiment at best (remember Silver City?). Nevada and LV specifically, are just trying to rebound. To ban smoking now would be a death knel and this comes from a 20 year nonsmoker. I think a good compromise would be more casinos with nonsmoking areas. At least this would offer an option without jumping into the lake headfirst.
Good Luck!
Ric at Joes