I wouldn't worry about it -- you're only getting about 1/10th the nicotine of a cigarette when you vape (from reports I've read, although some of them conflict, but it feels about right), plus, the nicotine hits you way slower than with a cigarette, so these vapes aren't really for giving you a quick buzz that wears off fast -- they're more for getting your nicotine level up to a point where you don't crave cigarettes -- and uhh, one other thing -- tasting frickin awesome and still letting you get your oral fix and blow smoke rings and whatnot
as for me, I'm not really the least bit concerned about how often I pick my ecig up and puff -- I do it literally whenever I think about it -- whereas when I was smoking
tobacco I had to constantly keep myself from smoking as often as I felt like because I knew how bad it was for me
not saying that if you vape like a chimney that it isn't 'bad' for you, but it's all relative -- you could probably never put it down and it'd still be way less bad for you than analogs -- just what I think though -- no science to back it up