to swallow or not to swallow?

Erin
Ladies.. 
I have never swallowed and I'm curious what it's like.. I have been in a relationship coming up on two years now with a wonderful man, who isn't the father of my child. He's always given me oral and goes until I cum. So I think it's time I return the favor. I've given him blow jobs before but have never swallowed. 
So, my question is what is it like to swallow?