I've been smoking blu brand e-cigs for about a year now. I still have the occasional Camel, but it is mostly just the e-cigs now.
One thing that probably needs to be kept in mind is that there are many brands, a lot of DIY kits, and modders out there. I just do the stock e-cigs from blu with their cartridges. I don't mod or refill on my own. I bring this up because occasionally I get someone who tells me, "Hey, those things blow up!" No, not really. I found a report of one doing it and it turns out it was some dip modder who tried to double the battery or something like that. I also like the fact that I know my 'juice' in my cartridges from blu are coming from a premium
American supplier and not some mystery place in the PRC that is probably lacing it with lead.
The e-cigs have no tar, no chemicals in the paper, no formaldehyde (no offense, Forma!) etc. They have no butts for people to flick out the window (I've never abided smokers that do that, but let's face it, most do,) and are a crap load cheaper than regular cigs. I pay roughly 1/2 as much as I was when I was just smoking Camels. That said, that tar and whatnot did give the real cigs that something extra that my blus are lacking, which I why I love my rare real Camel that I treat myself to.
Let's move on to nicotine, shall we? "It is a poison!" Yeah, well, so is chocolate. Per Wiki... "In smaller doses (an average cigarette yields about 1 mg of absorbed nicotine), the substance acts as a stimulant in mammals, while high amounts (50–100 mg) can be harmful." Guess what else has nicotine? Eggplant, tomato, potato, friggin' cauliflower.
So all in all, I think e-cigs are a huge plus. I don't personally push it and try to puff away in places that ban smoking even though it isn't smoking (no smoke, eh, it's water vapor with maybe a hint of nicotine... oh, you're eating a BLT, right) just because I know most people would irrationally flip out about it. That said, I probably won't be polite about it for long.
Second to last, I would like to address one part of the whole e-cig thing that really bugs me. The attempt to make it some cool social thing. Blu offers these fancy packs that actually allow you to load up your facebook profile and crap into them and sync it when it detects other blu users who have enabled their pack within a short distance. The pack can even be set to light up and crud. I do -not- like this aspect of it.
And now lastly... to the haters. Bugger off.
Whenever I see them getting used in coffee shops, buses, etc. (where smoking is of course not allowed) it disgusts me. Each time I'm slightly more tempted to make a scene about and demand they keep their poisons at home. Sure they are less disgusting than regular cigarettes, but their users act like that makes them somehow better. When they are still sick degenerates willfully poisoning themselves and everyone around them.
You're probably one of those that would yell at me from shore if I lit up in the middle of a lake while fishing from a boat. Don't worry, for what it's worth, you extremists disgust me too, so we're even.