If you are a step-dad, what does your step-kid call you? My daughter calls me 'dad'-she's never had a dad in her life, and I've raised her. Others find it odd. If her father was around I would too, but he's not and she chose to give me that title.
I think that's great and it's not odd, especially since her birth father isn't in the picture. I have a very close relationship with my 10 yr old step-daughter, but since the dad is available by phone, it would be a bit awkward for her.
The wife yells when she calls me Jason, but she also calls my wife her name from time to time too. Usually it is dad, daddy, or some form thereof. I've been the only father she has ever known.