I suspect that if they could find a way to extract MAOI alkaloids from tobacco, it shouldn't be any different (legally speaking) from current e-cigarettes. However, if they are adding other chemicals that are not approved tobacco additives, they might be forced to get approval as a drug or combination device.
Wasn't sure what was actually allowed to be added to cigarettes so....
The list of 599 additives approved by the US Government for use in the manufacture of cigarettes
The List of Additives in Cigarettes - Additives in Cigarettes
Intrestingly enough there's a number of flavors that ARE allowed, and this is with no flavored cigarettes??
Perhaps this list might be useful when it's brought up that flavors are evil.....
(I just picked out the obvious flavors from the list)
Almond Bitter Oil
Anise
Anise Star, Extract and Oils
Apricot Extract and Juice Concentrate
Basil Oil
Bay Leaf, Oil and Sweet Oil
Beet Juice Concentrate
Black Currant Buds Absolute
Caraway Oil
Carrot Oil
Chocolate
Cinnamon Leaf Oil, Bark Oil, and Extract
Cocoa
Coffee
Eucalyptol
Fennel Sweet Oil
Fig Juice Concentrate
Grape Juice Concentrate
Honey
Hops Oil
Kola Nut Extract
Lavender Oil
Lemon Oil and Extract
Lemongrass Oil
Licorice Root, Fluid, Extract and Powder
Lime Oil
Linden Flowers
Mandarin Oil
Maple Syrup and Concentrate
Molasses Extract and Tincture
Mountain Maple Solid Extract
Nutmeg Powder and Oil
Orange Blossoms Water
Orange Oil and Extract
Parsley Seed Oil
Patchouli Oil
Pepper Oil, Black And White
Peppermint Oil
Pine Needle Oil, Pine Oil, Scotch
Pineapple Juice Concentrate
Plum Juice
Raisin Juice Concentrate
Rose Absolute and Oil
Rosemary Oil
Rum
Rum Ether
Rye Extract
Sage, Sage Oil, and Sage Oleoresin
Sandalwood Oil, Yellow
Smoke Flavor
Snakeroot Oil
Spearmint Oil
Thyme Oil, White and Red
Vanilla Extract And Oleoresin
Vanillin
Vinegar
Violet Leaf Absolute
Walnut Hull Extract
Wild Cherry Bark Extract
Wine and Wine Sherry