Parent Teacher Conferences

My daughter, who is three years old, was put into preschool at two because she was EXTREMELY shy and disliked being talked to by strangers, etc.  This year, in the conference I had today with her teacher, her teacher tells me she regularly has to tell Emersen she needs to be quiet and save her comments until the story they are reading is over.  She has used the "zip the lips game."  Really?  My little child who was so far in her shell she would cry when talked to directly by people she does not know, now is the chatty one in class?

At what point is it inappropriate to wish she would go back in her shell just an inch or two?

And what is her brother going to be like, if she is the chatty one?  Usually, he is the one who never stops talking (even though he does not speak English - rather a baby language of some sort).