More and more American smokers are opting to get their nicotine fix using e-cigarettes instead of conventional smokes — and Big Tobacco is taking note. Several major tobacco companies have this year introduced their own versions of electronic cigarettes, joining a bevy of small purveyors who've been in the e-smoke business for years. And with Big Tobacco entering the fray, new estimates suggest the e-cigarette industry will crack $1 billion in revenue this year, and that sales could outpace traditional cigarettes by 2047.

That's the crux of a new report from Bloomberg Industries, which estimates that if e-cigarette sales continue to grow at their current pace, these smokeless devices will one day be the top nicotine delivery mechanism for Americans still in need of a fix. And while 2047 might seem like a long way off, it's actually a remarkably disruptive timeframe when you consider that traditional cigarettes have been around for centuries, while e-cigarettes were only invented a decade ago. "E-cigarettes are more than just a fad," reads a recent report from Wells Fargo. "E-Cigarettes' appeal stems from a variety of perceived advantages over traditional cigarettes, most commonly the perceptions that e-cigarettes are healthier, cheaper, and can be used almost anywhere."

But those perceptions might soon change, and that could thwart the industry's growth. The Food and Drug Administration (FDA) is currently developing a framework of regulations, which should be completed in October, to clamp down on how e-cigarettes are marketed and sold. Several states are pushing to tax e-cigarettes, in much the same way that legislators have imposed levies on traditional cigarettes. And researchers are still investigating, and debating, whether or not smokeless cigarettes are actually healthier than their counterparts. The American Cancer Society, for instance, is urging that the FDA conduct additional research "to determine if e-cigarettes are safe for use," and to investigate "their potential as cessation aids."