You'd still be an addict, just one who could never satisfy his cravings. This sounds more like some sort of torture that an aid to quitting.
You will always be an addict. I quit smoking over 3 years ago, and I'm still addicted. After trying various ways of quitting, I ended up talking to a doctor and got Champix prescribed to be, which ended up helping a lot and making it possible for me to quit. When I did quit, the days I suffered the most were when my body was flushing the nicotine out. For this part, a vaccine like this would have been wonderful. Instead of having cramps and throwing up for 2 days (yes, this kind of abstinence syndrome can happen even with nicotine), and still suffering for several days afterwards, it would have made it much easier.
So yeah, I do wish this vaccine existed when I quit, 3 years ago, after smoking 2 packs/day for 20 years.
Some of what you say is very true, but you are wrong the withdraw will be bad, and I mean BAD with all capitals. I also foresee some more subtleties to this treatment....The idea is to uncouple the reward mechanism from the stimulus (nicotine hits receptors and triggers a dopamine surge which is perceived as a reward) - no reward, you stop associating smoking with pleasure. Straightforward. The immune system should be capable of removing most of the nicotine and preventing any large response. So what can go wrong....well you're dealing with humans. So....
1. The withdraw will be swift and the worse possible cold-turkey (which, short of using medication is the best way to quit). You will not get relief with patch, gum, smoking, snuff, hanging out with other smokers to get a second hand hit, or chewing on a raw tobacco plant, etc. You might get some relief with buproprione (considered a mild dopamine re-uptake inhibitor, but some controversy there) and probably more relief with varenicline(Chantix(tm)) (which is a weak nicotine agonist). This withdraw may feed into #2. It is also conceivable that some people could hurt themselves by trying to smoke so much to get even a little relief, that they could wind up in the hospital with carbon monoxide poisoning or acute exacerbation of underlying pulmonary disease. The vaccine will reduce the reward, but will do nothing for the craving.
2. The effects of the vaccine may require boosters. So you would be required to go back to get them, otherwise you would likely loose the immune response and would again get a "reward" for smoking. This could lead to avoidance of the vaccine and relapse.
3. The tobacco industry will probably fight this tooth and nail. It won't be overt....no, they'll buy a few select individuals who will tank it via the FDA.