Okay, so based on those articles there are still a lot of unknowns, however the general consensus is that vapor (from an cigalike-type device, aka 808D vape pen) contains anywhere 10% to 50% of the nicotine that cigarette smoke contains. Additionally, the nicotine in vapor is less easily absorbed by the lungs than that in cigarette smoke due to the size of the particulates (1 micron for smoke and 10 microns for vapor).
As such, even if you hold the vapor in your mouth, followed by an inhale, followed by an exhale through the nose to maximize nicotine absorption, you should be able to get anywhere from 2-10 times as many puffs from a cigalike than a cigarette and get about the same amount of nicotine. To put that in practical terms, if we assume you get about 10 puffs off a cigarette, then that would equate to 20 to 100 of equivalent-sized puffs from a cigalike. Since most commercial cartomizers are constructed in a similar manner, I imagine that the wide margin is due to the different levels of nicotine that juice can have (Vuse uses 48mg juice in some flavors, Blu can be anywhere from 12mg to 24mg, etc).
Naturally, you'll get fewer puffs from higher nicotine content and/or mods that produce a lot of vapor, but that still assumes your doing the triple-level inhale when you vape. Direct-to-lung hits will result in less nicotine absorption than what the above statements suggest, which is how I was vaping until I read those articles.