Who is the mandy people keep referring to?

Hey Mandy,
Who are ya?

If you check the advisors section you'll find a description of who MM is. She is a singer/songwriter/actress who recently can be seen in 'License to Wed' with John Krazinski from The Office and Robin Williams. She was also recently in 'Because I Said So' with Diane Keaton. She is currently on tour for her newly released album 'Wild Hope' and is getting publicity through radio/chats/online sites, etc.

Mandy Moore. Singer, actress. Brown hair, brown eyes. Pretty. =)

...the prettiest.

They are referring to Mandy Moore.