What does it mean when he calls me doll?

So I've been web-caming with this guy for a while now, because he lives in Cali and I in Michigan, so it's kinda hard to see each other if you know what I mean. Anyways, I can tell that we're both really comfortable with each other, we talk about everything pretty much and we talk everyday like it's our job or something. Love it, I just can't tell if he really likes me or not. He's kinda hard to read. Then last night I sent him an email saying goodnight cause it was late. When I woke up, I had a reply that said "goodnight doll! :) ". What I need to know is, I don't know if him calling me a doll is a good thing or not. I mean guys, do you say that to just anyone? Am I think too much into this? Thanks for your help, it will make my decisions much easier :)