Interesting...I am drinking a real coke now (it was leftover), which is unusual. I am actually partial to Pepsi/Mt Dew products (diet). I have long been addicted to soda. I just love the bubbles and bite, but I'm aware of the bad effects too. It's my main vice, so that puts it in perspective.
Recently I got a Primo flavorstation (like a sodastream, but cheaper to refill CO2 $4 @ dicks sporting goods). I love this thing. The sodas taste fresher (I buy sodastream and primo flavors) and now when I drink regular drinks I find I don't like them as much (maybe the sodium?). Anyway..I feel a little healthier as a result, but I don't feel that addiction as much. I make what I want, when I want. This is my 3rd month. Its not really the caffeine I crave, so much as the taste and the carbonation.
If anyone wants info about them feel free to PM me.
I would find it hard to quit soda cold turkey. With this you could use lemon juice, tea or other natural flavors and ween yourself off.
Ultimately I'd like to find flavors with Stevia or some other natural calorie free sweetener though.