What's the current data on the negative effects of vaping? I know it hasn't been out long yet, but I think nicotine has some slight negative effect, and then others complain about the polyethylene glycol.

Especially useful would be to see a burn-down chart of say, new smokers and new vapers of the same age range, and seeing cumulative lung disease and mortality, and seeing how the progress of that differs (or is the same).