not a bad message back, just spice it up a bit.
something like:
"ah you're one of those girls aintcha? Yeah, Coldplay is pretty amazing...*insert neg or comment here*
the key is to make a comment or point that keeps them confused and wondering. shes almost guaranteed to answer with "what kind of girl?" to your comment.
by the way, when she does respond with that don't answer the question...just ignore it and keep the conversation going.
for the *insert comment here* part, find something on her page that you can make fun of and comment on it....i.e. her interests, profile pic, music taste, movies, etc.
heres one of my examples...a girl had a picture of one of the Jonas Brothers members on her page, so i left this comment
"i see you like that dude from the disney channel up there. nice choice going for the underage ones, pedophile
"this comment negged her on her profile and playfully made fun of her.....try it out and see how you do.