Are online casinos destined to outlast land-based casinos, or will it eventually emerge that online gambling is the fad that the industry's critics say it is? Is it possible to measure the longevity of a still growing phenomenon, and is it correct to do so at such a juncture in that phenomenon's history? To be perfectly frank, it is a pretty difficult thing to do, and any conclusions wouldn't exactly based on the available facts but rather on speculation and the biases of those doing the predicting. For example, one who is opposed to online casinos might be inclined to, despite conclusions to the contrary, say that the online gambling industry's days are numbered.
Of course, you also have the possibility of an online casinos enthusiast's biases getting in the way of evidence that would point to a decline, though not a disappearance, of the online gambling industry. They might be inclined to ignore certain facts which point to a conclusion that pro-online casinos analysts don't want to agree with, and they might inflate revenues to make it appear to readers that online casinos are doing better than they actually are. That wouldn't be illegal, as long as they aren't a company, but it wouldn't be in line with principles of honesty.
Basically, you can't really predict what course online casinos will take as the online gambling industry is really only at the beginning of its lifespan. It may be a fad, and it may not. The numbers, in the billions of dollars and euros and pounds, are impressive. But many a company and industry has been known to virtually lose all of the money it has made and virtually disappear overnight - and unfortunately, online casinos are not immune to such an outcome, no matter how much online gambling enthusiasts and online casino executive boards might choose to believe otherwise.
