I can't speak for her, but I'm assuming on vmk...b/c I rarely see people in real life going up to strangers asking "are you taken"? Since we don't know who a person *really* is on vmk, we can only see their avatar (character), that to me is the equivalent of calling a random person in the phone book, without seeing their name, and asking if they are taken before they can say "hello". Not exactly the same, but it's similar b/c like, you don't know who they are, what they look like, how old they are, or even if they are male or female! I know on vmk it's just pretend, no one is actually dating, but I am so against the taken thing (if you know me, you probably already know that! I scold girls for it all the time

).
I'm sure being "taken" is harmless, because even if an 11 year old girl's vmk boyfriends is actually a 54 year old man or a FEMALE even (I mean, I have some boy characters and mules....who by the way get hit on ALL the time b/c of course they are 'cute') then she will never know it. She can imagine it's a cute little 11 year old boy who looks like the avatar. But most times, sorry to say, it's not. And even if being taken were ok with me, I still think that the random "u taken?" as a first greeting is silly. If you want to pretend like you are dating in real life, make friends, hang out, then decide if you like each other and be a pretend couple!
And let me add that I cannot stand how almost every girl has a signature like "I am cute and a cheerleader and not taken, come get me boys" to attract them. It makes them look foolish and desperate, like Kat said.
Just play the game, make friends, have fun. Don't try to grow up too fast and if you must have a boy or girl friend on vmk, at least talk a little first! How about, "Hi, I'm so and so, nice to meet you"???
And don't even get me STARTED on the "mummy duh-duh bay be" junk.
~Mia steps off the soapbox~