I think the type of smoker you were plays a big part-- how long and how much you smoked. I was a 15-lite cig-a-day (just under a pack) smoker, and smoked for about 12 years. I quit the day after my kit arrived and was charged (9/12/2010). It was easy for me: I had no cravings for a cig and still don't.
The biggest difference I noticed was I was chain vaping, where as I wasn't a chain smoker. I smoked one cig about every two to three hours. I found out this was partly because my body was craving some of the other addictive chemicals in cigs that aren't in e-cigs; and partly it was because I needed to raise my juice's nic levels (I went with "light" levels (11mg/ml) because that was what I smoked.) I found that for me 24mg allowed me to go back to a schedule I was more used to. I'm now vaping four or five drags every hour-- which is close to what I was doing in analogs: 8 puffs of a cig every two hours or so.
I also think the higher your OCD level, the harder it will be. The vaping “ritual” is very close to the smoking ritual, but not exactly the same: no lighters; drag is way different; no head rush on first hit; etc. If you are a hardcore OCD, you will probably have trouble with the small differences in the ritual. I noticed the differences, but they didn’t bother me.
I plan to lower the nic levels later and eventually quit, but not because I don't want to be "hooked on nicotine" (I personally don't see anything wrong with nicotine; in my opinion, it's up there with caffeine as a drug: in moderation, it is a safe, feel-good drug people like); I'm going to quit because I don't want to get stuck in the lurch if my stupid on-the-take government decides to ban e-cigs (or, almost as worst, figure out a way to tax the crap out of it to make up for all the money it's going to lose as people start quitting tobacco).
I do think it will be much easier to quit e-cigs than analogs: I've already noticed that if I get stuck in a situation where I can't vape for three or four hours, I don't get that uncontrollable how-do-I-get-out-of-here anxiety I used to get as a smoker; Instead, I find it's much easier to occupy myself and put the craving out of my mind.
The only thing I miss from analog smoking is the convenience. Don't let anyone tell you otherwise: No matter what electronic system you go with, it's going to require way more "work" to keep yourself vaping from day-to-day. Cigs were easy: your only worry was having a way to light it. If you got stuck with no cigs and/or no lighter, a store or a good samaritan was always nearby to help you out. Not with vaping.