I've met Rosie in person on at least four occasions, Entmoot included, have known her real name for over a year, and I STILL call her Rosie when I'm with her!! It's easier for me cause my screen name was my nickname when I was younger.
*chuckle*
I think it's the fate of most internet nicks, few of them fail to cross over into the physical world. When my friends get together, I end up answering to Empress, Emp, E, EC and other such variations even more commonly than my first name.
It was funny at entmoot, when people would use screennames and real names pretty much interchangably... I never could remember to call Ramius anything but Ramius, even if I remembered other people's names. Wonder why that was.