I am not an introvert but I love and respect a great many people who are. I wish more people would understand what it means to be an introvert - maybe you are and you don't even realise. Introversion does not equal shyness.
Introverts are capable of acting like extroverts for the sake of work they consider important, people they love, or anything they value highly. We can extrovert the hell out of something interesting and worthwhile, for a period.