Well since people said it ambiguously or slightly correctly I'll just say it anyway.
A while back, the forums had a setting to hide what you're doing in the Who's Online section. It's a standard feature of SMF. Badspot disabled the setting though, so users couldn't change it anymore. It's still saved though, so users with it enabled have an italic name there.
It's because back then you had a forum option where you could set yourself as "Private" and not appear on the "Who's online" board. It seems that tails did this and now his name is in italics. It's also the same thing for other people who's names are in italics. I'm fairly sure Badspot already said this.
go away
