I'd like to respond to Mizzou's questions in the "Effectivness" thread.
So far as it being a quit tool; for me it was more like a superior replacement for smoking rather than a cessation aid. It quickly became far more enjoyable than smoking ever was. But since I was able to completely eliminate smoking within 2 months, and have remained so without a single relapse, then yes, it was a highly effective cessation aid.
As for the effectiveness; I measure it for me by the ease of transistion, the effectiveness at quelling cravings, and it's ability to keep me smoke-free over the longterm. E-cig have excelled in each of these; a near seamless transition, 100% elimination of cravings, and 100% smoking cessation over a period of 20 months.
I do not consider my continued use of nicotine to be a significant factor in my ability to remain smoke-free. Even the makers of NRT products are currently working to have NRTs approved for long term or even permanent use, and preliminary reports suggest that approval is likely.
Further, new studies suggest that nicotine and other alkaloids in tobacco may actually be beneficial to some. Other studies suggest that for some long-term smokers, irreversable permanent changes may have occurred in brain chemistry, such that continued use of reduced-harm tobacco alternatives and/or other replacement drugs may be necessary to maintain quality of life.
To answer your question succintly... I believe the effectiveness of e-cigs should be measured only by their ability to help a smoker achieve and maintain smoking abstinence, not nicotine abstinence. Once the cycle of smoking is eliminated, any dependency on nicotine can be managed separately over time, at one's own pace.
Oh, and @Brad... I may very well continue to use nicotine, along with possibly the other relatively harmless compounds contained in tobacco that are showing promise for medicinal value, for the rest of my life. I can guarantee, though, that I won't be dying from nicotine, and certainly not from cigarette smoke.